Maemo 5 Final SDK 安装指南

(自Maemo 4.x/Diablo SDK升级)
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本文是[[Documentation/Maemo 5 Final SDK Installation]]的简体中文翻译。
本文是[[Documentation/Maemo 5 Final SDK Installation]]的简体中文翻译。
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以下文档介绍了如何安装Maemo 5 Final SDK。Maemo SDK,使用安装了Maemo特有的开发文件的Scratchbox,做为交叉编译环境。
+
以下文档介绍了如何安装Maemo 5 Final SDK。Maemo SDK使用Scratchbox作为交叉编译环境,你还需要安装Maemo的开发文件。
在开始安装以前,先来看一下最小的系统需求。官方支持基于Debian的x86-32 Linux发行版,主要是Debian和Ubuntu。但在其他Linux发行版上安装Maemo SDK也是可以做到的。
在开始安装以前,先来看一下最小的系统需求。官方支持基于Debian的x86-32 Linux发行版,主要是Debian和Ubuntu。但在其他Linux发行版上安装Maemo SDK也是可以做到的。

Revision as of 04:30, 28 January 2010

Contents

介绍

本文是Documentation/Maemo 5 Final SDK Installation的简体中文翻译。

以下文档介绍了如何安装Maemo 5 Final SDK。Maemo SDK使用Scratchbox作为交叉编译环境,你还需要安装Maemo的开发文件。

在开始安装以前,先来看一下最小的系统需求。官方支持基于Debian的x86-32 Linux发行版,主要是Debian和Ubuntu。但在其他Linux发行版上安装Maemo SDK也是可以做到的。

当你确定你的开发设备符合这些要求后,你可以按照以下指南操作。

Maemo 5 SDK配备了两个命令行安装脚本,以及一个附带图形界面的安装程序(仍是beta版本),以简化SDK的安装。

  • Scratchbox安装脚本将在你的机器上自动下载、安装指定版本的Scratchbox。
  • Maemo SDK安装脚本将在Scratchbox里设置两个编译目标(armel和x86),为这两个目标下载最基本的开发文件包rootstraps,并安装用户指定的开源开发工具。
  • 图形界面的安装程序会同时安装Scratchbox和Maemo SDK。


Maemo 5 SDK通过一个需要认证的软件源,提供了开发者所需要的Nokia二进制开发文件包,以及附带的Nokia应用程序。为了获取这些文件,你需要接受 Nokia的最终用户许可协议。为了获得Maemo SDK的完整功能,你需要这些开源工具包以外的Nokia二进制文件包。


Maemo SDK没有包含的内容

在你的主机上执行Maemo SDK程序需要Xephye这个X11服务器。这个X11服务器提供了一个窗口,显示设备屏幕和用户界面,使得开发者可以在自己的主机上看到Maemo程序窗口和界面。这个软件没有包含在Maemo SDK内,因为绝大多数Linux发行版都提供了这个软件。

如果你在基于Debian的Linux发行版上,通过图形界面的安装程序安装Maemo SDK,将为你提供安装Xephyr的选项。

如果不是,你可以采用以下的方式,手工安装Xephyr。

在基于Debian的Linux系统上,可以在Scratchbox环境外,以root权限,使用apt-get安装Xephyr。

$ sudo apt-get install xserver-xephyr

在Gentoo系统上,你需要添加kdrive这个useflag,再编译xorg-server,以获得Xephye。

通过图形界面的安装程序安装Maemo 5 SDK

现在,Maemo 5 SDK拥有了使用方便的图形界面安装方式。这个安装程序可以在基于Debian的发行版上安装Scratchbox和Maemo 5 SDK。同时,也可以处理这个页面提供的Nokia最终用户协议,并安装Nokia的二进制开发工具包和应用程序。

图形界面安装程序拥有以下功能。

  • 安装/升级Scratchbox
  • 安装Maemo 5 SDK
  • 安装Nokia的二进制文件包
  • 安装Nokia应用程序
  • 安装Xephye
  • 在桌面上创建Xephye启动器
  • 在桌面上创建Scrachbox Home目录的快捷方式
  • 在桌面上创建对开发者有用的Maemo 5信息页

图形界面安装程序提供了标准安装和自定义安装两种选择。标准安装使用默认设置,而自定义安装提供了更多的选择。需要注意的是,如果存在 FREMANTLE_X86和FREMANTLE_ARMEL的编译目标,标准安装将会覆盖这两个目标,不过Scratchbox的home目录将会被保留。如果你不想覆盖这两个编译目标,请使用自定义安装。

安装程序是一个Qt程序,需要Qt的python绑定的支持。如果你的系统没有安装这些软件包,安装程序可以安装他们。

如果有需要,安装程序可以使用http代理。如果你的网络连接没有正常工作,安装程序将请求你手工设置代理。

安装程序在Ubuntu Karmic和Debian Lenny上经受了测试,32位和64位版本都可以正常使用。安装程序需要下载Maemo SDK,因此你需要一个可用的Internet连接。

开始安装

如果你要在一个非Debian系统上执行安装脚本,可能会缺少一些python的设置,从而无法自动定位scratchbox的安装路径。为了解决这个问题,你需要给这个脚本打一个补丁

以下是补丁文件。

129c129
< SB_PATH = "/scratchbox"
---
> SB_PATH = "/opt/scratchbox"
2297a2298
> opt = opt + "-s /opt/scratchbox"
2351a2353
> cmd = cmd +" -s /opt/scratchbox"

另外,你也应该去除安装Xephyr的选项,然后手工安装它。

使用wget下载安装程序。

$ wget http://repository.maemo.org/stable/5.0/maemo-sdk-install-wizard_5.0.py

为安装程序添加可执行权限

$ chmod a+x maemo-sdk-install-wizard_5.0.py


安装需要root权限。

Ubuntu
$ sudo ./maemo-sdk-install-wizard_5.0.py
Debian
$ su -c ./maemo-sdk-install-wizard_5.0.py


限制:

  • 因为安装程序需要进行软件包安装,你应该在安装前,先退出其他的包管理程序。
  • 需要注意的是,Scratchbox的路径检测并不完美,你必须将它安装在/scratchbox目录下。
  • 另外,安装程序需要pyQt的支持,老版本的Ubuntu和Debian可能没有提供pyQt。
  • 在64位系统上,安装程序将显示需要做哪些设置,但不会自动进行配置,你需要手工配置它们。
  • 安装程序会DISPLAY环境变量设置为":2",如果你想使用其他值, 请手工更改。

在基于Debian的x86-32 linux发行版上安装Maemo 5 SDK

1. 下载Scratchbox和Maemo SDK的安装脚本。你也可以在Nokia开发论坛(Maemo SDK at Forum Nokia)上下载到同样的脚本。

$ wget http://repository.maemo.org/stable/5.0/maemo-scratchbox-install_5.0.sh http://repository.maemo.org/stable/5.0/maemo-sdk-install_5.0.sh

2. 为脚本添加可执行权限。

$ chmod a+x ./maemo-scratchbox-install_5.0.sh ./maemo-sdk-install_5.0.sh

3. 以root权限运行Scratchbox安装脚本,同时指定需要添加到Scratchbox用户组的用户。该用户必须是宿主Linux系统中有效的用户。这将下载大约420MB的内容,不支持断点续传。

$ sudo ./maemo-scratchbox-install_5.0.sh -u USER

4. 安装脚本将会在“sbox”用户组中添加指定的用户。要使改设置在当前终端进程中生效,你需要执行以下命令。 注意:如果你已经登录进了Scratchbox环境,这个命令将改变当前的用户组ID。如果你不想改变,只要从Scratchbox环境中注销再重新登录即可。

$ newgrp sbox

这时,你已经获得了一个可用的Scratchbox环境。

5. 继续进行Maemo SDK的安装。这个脚本需要在Scratchbox环境外,以安装时指定的用户权限运行。首先,为脚本用户添加可执行权限。

$ sudo chmod +x ./maemo-sdk-install_5.0.sh

然后运行。

$ ./maemo-sdk-install_5.0.sh

如果你将Scratchbox安装到了/scratchbox以外的目录,你需要用“-s PATH”选项来指定你的Scratchbox目录。你可以使用“--help”选项获得更多的命令行选项信息。

6. 脚本成功执行完成后,你就可以登录Scratchbox环境了。

$ /scratchbox/login

如果你无法登录,请看一下Scratchbox的限制。

7. 你需要接受Nokia的最终用户许可协议,才能够获取Nokia提供的二进制软件包。安装这些软件包后,你将会获得Maemo SDK的完整功能。

7.1. 通过这个页面,接受最终用户许可协议。

7.2. 将接受最终用户许可协议后获得的软件源地址,分别添加到x86和armel两个编译目标环境的/etc/apt/source.list文件中。然后在两个目标的环境下,执行以下命令。


[sbox-FREMANTLE_X86: ~] > sb-conf select FREMANTLE_ARMEL
[sbox-FREMANTLE_ARMEL: ~] > nano /etc/apt/sources.list # add deb line
[sbox-FREMANTLE_ARMEL: ~] > apt-get update
[sbox-FREMANTLE_ARMEL: ~] > fakeroot apt-get install nokia-binaries nokia-apps
[sbox-FREMANTLE_ARMEL: ~] > sb-conf select FREMANTLE_X86
[sbox-FREMANTLE_X86: ~] > nano /etc/apt/sources.list # add deb line
[sbox-FREMANTLE_X86: ~] > apt-get update
[sbox-FREMANTLE_X86: ~] > fakeroot apt-get install nokia-binaries nokia-apps

以上步骤将安装Nokia的二进制文件包,一些开源工具包依赖它们。这样,你就完成了Maemo 5 SDK开发环境的配置,可以动手进行开发了。

在openSUSE上安装Maemo 5 SDK

这是来自opensuse.org的安装指南。

启动/终止SDK图形用户界面

在启动用户界面前,请先确认你已正确安装了以下内容:

  • Scratchbox环境外,宿主系统上的Xephyr X11服务器
  • 之前提到的SDK
  • Nokia二进制工具包

1. 首先,在Scratchbox环境外,启动Xephyr:

Xephyr :2 -host-cursor -screen 800x480x16 -dpi 96 -ac -kb &

2. 登录Scratchbox的X86编译目标环境

$ /scratchbox/login
Welcome to Scratchbox, the cross-compilation toolkit!
Use 'sb-menu' to change your compilation target.
See /scratchbox/doc/ for documentation.
[sbox-FREMANTLE_X86: ~]>

3. 设置DISPLAY环境变量,使之与Xephyr的设置相符。

[sbox-FREMANTLE_X86: ~] >export DISPLAY=:2

4. 启动用户界面。

[sbox-FREMANTLE_X86: ~] >af-sb-init.sh start

5. 图形界面将出现在Xephyr窗口中。

6. 你可以用如下命令终止用户界面:

[sbox-FREMANTLE_X86: ~] >af-sb-init.sh stop

在基于Debian的x86-32 linux发行版上安装Maemo 5 SDK

由于Scratchbox只支持x86-32架构的linux宿主系统,因此,在x86-64系统中,我们需要强制安装x86-32的Scratchbox软件包。在执行Scratchbox的安装脚本时,添加“-F”选项即可。

安装流程

  • 下载Scratchbox和Maemo 5 SDK的安装脚本。
$ wget -c http://repository.maemo.org/stable/5.0/maemo-scratchbox-install_5.0.sh http://repository.maemo.org/stable/5.0/maemo-sdk-install_5.0.sh
  • 为脚本添加可执行权限
$ chmod a+x ./maemo-scratchbox-install_5.0.sh ./maemo-sdk-install_5.0.sh
  • 以root权限运行Scratchbox安装脚本,并添加“-F”选项,同时指定需要添加到Scratchbox用户组的用户。该用户必须是宿主Linux系统中有效的用户。
$ sudo ./maemo-scratchbox-install_5.0.sh -F -u $USER

在成功安装Scratchbox后,请参照x86-32系统的安装指南,继续安装Maemo 5 Final SDK。

在非Debian系统中启动Scratchbox

如果通过Debian的deb包安装了Scratchbox,Scratchbox的启动脚本/etc/init.d/scratchbox-core将被正确安装,Scratchbox也会在系统重启时自动启动。

如果你通过tarballs的方式安装了Scratchbox,那么当系统重启后,Scratchbox需要的挂载配置和binfmt_misc都将被清除。

要使Scratchbox在重启后继续工作,你需要以root权限执行以下命令:

$ sudo /scratchbox/sbin/sbox_ctl start

此外,你也可以将sbox_ctl作为一个系统脚本,添加到/etc/init.d目录下,并在对应的运行等级目录中创建链接。在大多数系统中,方法如下:

$ ln -s /scratchbox/sbin/sbox_ctl /etc/init.d/scratchbox-core
$ /usr/sbin/update-rc.d scratchbox-core defaults

请查阅你的系统文档,以了解相应的方法。

自Maemo 5 Beta 2 SDK升级

很不幸地,从Beta 2平滑地升级到Final SDK是不可能的。因此我们建议你重新安装Final SDK。在你操作以前,请先看一下下列指引。

一些随Final SDK附带的Nokia应用程序使用了固定的路径,来指定用户的home目录。为了使这些程序能够正常工作,你需要创建一个目录,路径与Nokia指定的路径相同。

这需要在Scratchbox环境外,以root权限操作。

Scratchbox安装脚本的“-u”选项将更新环境并创建必要的链接。

执行以下命令,为已有的Scratchbox用户创建必要的链接。

$ sudo ./maemo-scratchbox-install_5.0.sh -u <EXISTING_USER> 

此外,你也可以手动创建链接。如果Scratchbox被安装在了默认路径下,那么命令如下:

$ sudo ln -s /scratchbox/users/<username>/home/<username> /scratchbox/users/<username>/home/user

Final SDK的安装脚本也在/target/<target_name>/目录下添加了/opt目录。

为了便于在/opt路径下安装应用程序,一些linux系统会创建一个指向/home/opt的链接作为/opt目录。SDK也继承了这一特性。

在Scratchbox环境下,/opt目录的路径是/target/<target_name>/opt。

安装基本系统包rootstraps后,所有编译目标环境的/target/<target_name>/opt都将被指向/home/opt。而/opt应该为每个编译目标环境分别指定。

为了解决这个问题,我们需要手工检查/target/<target_name>/opt是否被链接了,如果是,那么删除这个链接,并且重新创建相应的目录。

自Maemo 4.x/Diablo SDK升级

事实上,由于API的变动,我们无法从Diablo升级到Fremantle。不过我们可以利用Diablo的Scratchbox环境,帮助配置Fremantle的Scratchbox环境。

所以,我们可以升级Scratchbox。

  • 下载Maemo 5的Scratchbox安装脚本
$ chmod a+x ./maemo-scratchbox-install_5.0.sh
  • 为脚本添加可执行权限,然后这样执行:
$ sudo ./maemo-scratchbox-install_5.0.sh -U -u <EXISTING_USER> -s /scratchbox

当脚本执行成功后,继续进行Maemo 5 Final SDK的安装。

施工中

[edit] Manual Installation

On x86-32 Debian based systems:

   * You can add the following line into your host machine's /etc/apt/sources.list file. 

deb http://scratchbox.org/debian/ maemo5-sdk main


   * Install the needed Scratchbox packages with root permission 

$ sudo apt-get update $ sudo apt-get install scratchbox-core scratchbox-libs scratchbox-devkit-qemu scratchbox-devkit-debian scratchbox-devkit-doctools scratchbox-devkit-perl scratchbox-toolchain-host-gcc scratchbox-toolchain-cs2007q3-glibc2.5-arm7 scratchbox-toolchain-cs2007q3-glibc2.5-i486 scratchbox-devkit-svn scratchbox-devkit-git scratchbox-devkit-apt-https


On x86-64 Debian based systems:

   * Download the Scratchbox packages from here. 
   * Force the installation of the x86-32 packages with root permission as follows: 

$ sudo dpkg -i --force-architecture scratchbox-core scratchbox-libs scratchbox-devkit-qemu scratchbox-devkit-debian scratchbox-devkit-doctools scratchbox-devkit-perl scratchbox-toolchain-host-gcc scratchbox-toolchain-cs2007q3-glibc2.5-arm7 scratchbox-toolchain-cs2007q3-glibc2.5-i486 scratchbox-devkit-svn scratchbox-devkit-git scratchbox-devkit-apt-https


The Scratchbox packages will be unpacked to /scratchbox directory and the installation procedure will ask you some questions about the group and user accounts. Default group to Scratchbox is 'sbox'.

   * Users who will be using Scratchbox should be added using the following command with root permission: 

$ sudo /scratchbox/sbin/sbox_adduser USER yes


It will automatically include the user to the Scratchbox group, create user directories under /scratchbox/users and mount several directories (/dev, /proc, /tmp) under the user directory.

   * Some of the Nokia applications shipped with the final SDK use a hard coded path for user home directory which presents a problem since the default username on the device differs from the username on the developer’s machine. To make these applications work, it is required to create a home directory that matches the hard coded value. This needs to be done outside scratchbox using root privileges. 

$ sudo ln -s /scratchbox/users/<username>/home/<username> /scratchbox/users/<username>/home/user


   * For the group membership to be effective in the current terminal session, run the following command: 

$ newgrp sbox

Note: This command will change the existing group ID during the current login session to 'sbox'. If you do not want to change, simply logout and log back in for the group membership to be effective.


   * Log-in to Scratchbox. 

$ /scratchbox/login


   * Configure the scratchbox x86 and armel targets as follows: 

[sbox->:~]>sb-conf st FREMANTLE_X86 -c cs2007q3-glibc2.5-i486 -d perl:debian-etch:doctools:svn:git -t none [sbox->:~]>sb-conf st FREMANTLE_ARMEL -c cs2007q3-glibc2.5-arm7 -d qemu:perl:debian-etch:doctools:svn:git -t qemu-arm-sb


   * Download the minimal rootstraps. 

[sbox->:~]> wget http://repository.maemo.org/stable/5.0/armel/maemo-sdk-rootstrap_5.0_armel.tgz http://repository.maemo.org/stable/5.0/i386/maemo-sdk-rootstrap_5.0_i386.tgz


   * Switch to x86 target, install the devkits, etc and fakeroot into the target, install the minimal rootstrap and finally the Maemo development files. 

[sbox->:~]> sb-conf se FREMANTLE_X86 [sbox-FREMANTLE_X86: ~] > sb-conf rs maemo-sdk-rootstrap_5.0_i386.tgz

   * Some users seem to have problems downloading all files with apt http pipelining enabled. If you want to make sure or you get download errors like "104 connection reset by peer" at the fakeroot steps below, then disable http pipelining with the next command: 

[sbox-FREMANTLE_X86: ~] > echo 'Acquire::http::Pipeline-Depth "0";' >> /etc/apt/apt.conf.d/00maemo

   * either way, continue here: 

[sbox-FREMANTLE_X86: ~] > sb-conf in -edFL [sbox-FREMANTLE_X86: ~] > apt-get update [sbox-FREMANTLE_X86: ~] > fakeroot apt-get install maemo-sdk-debug


The meta-package 'maemo-sdk-debug' installs all needed open source runtime, development and debug pakcages into the target. Use maemo-sdk-runtime if you want only runtime packages to be installed or user maemo-sdk-dev if you want only the runtime + development packages to be installed.

   * Accept the EULA from here to obtain the URL to access the Nokia binaries repository. 
   * Add the URL thus obtained to the Scratchbox target's /etc/apt/sources.list and do the following: 

[sbox-FREMANTLE_X86: ~] >apt-get update [sbox-FREMANTLE_X86: ~] >fakeroot apt-get install nokia-binaries nokia-apps


   * In order to facilitate installing applications under /opt on the device, a symlink /opt has been created pointing to /home/opt. The SDK inherits this feature. Under Scratchbox, /opt points to /target/links/opt which in turn points to /targets/<target_name>/opt. Installing the rootstraps makes this point to /home/opt, which is not what we want, since we need /opt to be target specific. In order to resolve this situation, 

[sbox-FREMANTLE_X86: ~] >rm /targets/FREMANTLE_X86/opt [sbox-FREMANTLE_X86: ~] >mkdir /targets/FREMANTLE_X86/opt


   * Execute similar steps on the armel target too to set it up: 

[sbox-FREMANTLE_X86: ~]> sb-conf se FREMANTLE_ARMEL [sbox-FREMANTLE_ARMEL: ~] > sb-conf rs maemo-sdk-rootstrap_5.0_armel.tgz

   * again,the next command disables http pipelining, if you like: 

[sbox-FREMANTLE_X86: ~] > echo 'Acquire::http::Pipeline-Depth "0";' >> /etc/apt/apt.conf.d/00maemo

   * pipelining disabled or not, here we go again... 

[sbox-FREMANTLE_ARMEL: ~] > sb-conf in -edFL [sbox-FREMANTLE_ARMEL: ~] > apt-get update [sbox-FREMANTLE_ARMEL: ~] > fakeroot apt-get install maemo-sdk-debug


   * Add the same URL obtained above to access the Nokia binaries repository under /etc/apt/sources.list file of the Scratchbox armel target. 

[sbox-FREMANTLE_ARMEL: ~] >apt-get update [sbox-FREMANTLE_ARMEL: ~] >fakeroot apt-get install nokia-binaries nokia-apps


   * Create the /opt directory. 

[sbox-FREMANTLE_ARMEL: ~] >rm /targets/FREMANTLE_ARMEL/opt [sbox-FREMANTLE_ARMEL: ~] >mkdir /targets/FREMANTLE_ARMEL/opt


With this, you must now have both the targets setup and ready to use.

Start the UI framework. [edit] Un-installation

Make sure that you have no process running inside Scratchbox. Uninstalling Scratchbox will remove everything that is installed and saved inside Scratchbox. Please take a backup of your files from Scratchbox user home directory if needed.

On Debian based systems, do the following with root permissions: $ sudo apt-get remove scratchbox-* --purge $ sudo rm -rf /scratchbox


On non-Debian based systems, you need to stop scratchbox as follows before removing it. $ sudo /scratchbox/sbin/sbox_ctl stop $ sudo rm -rf /scratchbox


[edit] Limitations of Scratchbox

The following limitations have been noted in the usage of Scratchbox: [edit] VDSO support

Scratchbox does not work when VDSO32 support is enabled in the host's kernel. We're working on making it possible, but at the moment there are some workarounds, which are presented here.

If your host has VDSO32 turned on you will get an error like this when trying to login to Scratchbox. No directory, logging in with HOME=/ Inconsistency detected by ld.so: rtld.c: 1192: dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!


[edit] x86-64 kernel

x86-64 Linux kernels starting from version 2.6.25 enable VDSO32 by default. To temporarily disable VDSO32 execute sysctl abi.vsyscall32=0

On Linux kernel 2.6.24 <= you can disable VDSO32 by executing sysctl vm.vdso_enabled=0

or sysctl kernel.vdso=0

The current setting of VDSO32 can be verified by using sysctl. Only values 0 and 2 are compatible with Scratchbox. In our examples we use 0 (disable). 2 enables compat mode.

You can set all of these permanently by adding the following lines to /etc/sysctl.conf vm.vdso_enabled = 0 abi.vsyscall32 = 0 kernel.vdso = 0

Save the file and run the command: $ sudo sysctl -p

Please note the correct line depends on your Linux kernel version. When you execute sysctl -p you may get a warning about unknown keys. You can safely ignore those warnings as long as one of the 3 settings works.

WARNING : You should try setting these values by echoing them to the given locations before adding them to sysctl.conf to see if they cause any problems. For example, in some Ubuntu Gutsy installations, it has been observed that changing the VDSO settings will hang the system and thus making permanent changes in sysctl.conf may, in these cases, make your system unbootable.


[edit] Known Issues in the SDK

   * A list of issues and their solutions is http://wiki.maemo.org/Q%26A_-_SDK_and_Scratchbox 
   * Unnecessary warnings and debugging messages are printed out when the hildon application framework is started. 
   * Armel target does not bring up the UI framework 
   * It has been noted that Xephyr dies with the application framework at times. The crash in question might even be Xephyr related since the application framework behaves differently with different versions/builds of Xephyr. The case seems to be worst on Xephyr that comes with Ubuntu Jaunty, there Xephyr will die when running any application that contains an input field and clicking on that field with a mouse to invoke the input method. On Fedora Code 10 the Xephyr does not mind the mouse clicks but dies when shutting down the application framework. On the other hand Xephyr on Ubuntu Intrepid or even the Intrepid version recompiled for Jaunty does not experience crashing in these situations. 

A patch is already available for the Xephyr on Ubuntu Jaunty and can be found at http://bugs.freedesktop.org/show_bug.cgi?id=21591. Binaries packages for xserver-xephyr package and its dependencies (libgpg-error0 and libcrypt11) can be download from Ubuntu Jaunty repositories.

   * The performance of clutter can be improved by enabling hardware acceleration if not enabled already. In some cases, it would require installing restricted/proprietary drivers (Eg: on host machines with ATI or NVidia graphics card). Refer to Maemo5 clutter performance for more details. 
   * Running Xephyr with -kb option disables entry of “@” symbol. However, removing -kb option disables cursor keys. 
   * Colours invert sometimes in some applications. (Browser and Photo's for example)