将 XFCE 桌面（包：xubuntu-desktop）与 GNOME 桌面（包：ubuntu-desktop）一起安装：ubuntu-desktop 中断

问题

我想将 XFCE 界面与 Ubuntu 预装的 GNOME 界面一起安装。

但是，当我尝试安装包xubuntu-desktop时，我最终得到了这个：

[kahless]# aptitude install xubuntu-desktop
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Reading extended state information      
Initializing package states... Done
Writing extended state information... Done
The following packages are BROKEN:
  ubuntu-desktop 
The following NEW packages will be installed:
  a2ps{a} abiword abiword-common{a} abiword-plugin-grammar{a} 
  abiword-plugin-mathview{a} app-install-data-commercial aumix{a} 
  aumix-common{a} catfish exaile exo-utils{a} fortune-mod{a} 
  fortunes-min{a} gigolo gnumeric gnumeric-common{a} gnumeric-doc{a} 
  gtk2-engines-xfce libabiword-2.8{a} libaiksaurus-1.2-0c2a{a} 
  libaiksaurus-1.2-data{a} libaiksaurusgtk-1.2-0c2a{a} libexo-0.3-0{a} 
  libexo-common{a} libgdome2-0{a} libgdome2-cpp-smart0c2a{a} 
  libgtkmathview0c2a{a} liblink-grammar4{a} libotr2{a} libots0{a} 
  libpsiconv6{a} librecode0{a} libscim8c2a{a} libsdl1.2debian-alsa 
  libtagc0{a} libthunar-vfs-1-2{a} libwv-1.2-3{a} libxfce4menu-0.1-0{a} 
  libxfce4util-bin{a} libxfce4util-common{a} libxfce4util4{a} 
  libxfcegui4-4{a} libxfconf-0-2{a} libxmlrpc-core-c3{a} 
  link-grammar-dictionaries-en{a} mousepad murrine-themes{a} orage 
  oss-compat{a} pidgin pidgin-data{a} pidgin-libnotify{a} pidgin-otr 
  psutils{a} python-cddb{a} python-mmkeys{a} python-mutagen{a} 
  python-sexy{a} ristretto scim scim-bridge-agent{a} 
  scim-bridge-client-gtk{a} scim-gtk2-immodule{a} scim-modules-socket{a} 
  scim-modules-table{a} scim-tables-additional tango-icon-theme-common 
  thunar thunar-archive-plugin thunar-data{a} thunar-media-tags-plugin 
  thunar-thumbnailers thunar-volman{a} thunderbird ttf-lyx{a} usb-creator 
  xfce-keyboard-shortcuts{a} xfce4-appfinder xfce4-clipman{a} 
  xfce4-clipman-plugin xfce4-cpugraph-plugin xfce4-dict 
  xfce4-fsguard-plugin xfce4-mailwatch-plugin xfce4-mixer 
  xfce4-mount-plugin xfce4-netload-plugin xfce4-notes{a} xfce4-notes-plugin 
  xfce4-panel{a} xfce4-places-plugin xfce4-power-manager 
  xfce4-power-manager-data{a} xfce4-quicklauncher-plugin 
  xfce4-screenshooter xfce4-session xfce4-settings{a} 
  xfce4-smartbookmark-plugin xfce4-systemload-plugin xfce4-terminal 
  xfce4-utils{a} xfce4-verve-plugin xfce4-volumed xfce4-weather-plugin 
  xfce4-xkb-plugin xfconf{a} xfdesktop4{a} xfdesktop4-data{a} xfprint4 
  xfswitch-plugin xfwm4{a} xfwm4-themes{a} xscreensaver xubuntu-artwork{a} 
  xubuntu-default-settings xubuntu-desktop xubuntu-docs 
  xubuntu-gdm-theme{a} xubuntu-icon-theme{a} xubuntu-plymouth-theme{a} 
  xubuntu-wallpapers{a} 
The following packages will be REMOVED:
  libsdl1.2debian-pulseaudio{a} xaw3dg{u} 
0 packages upgraded, 121 newly installed, 2 to remove and 1 not upgraded.
Need to get 75.7MB of archives. After unpacking 261MB will be used.
The following packages have unmet dependencies:
  ubuntu-desktop: Depends: libsdl1.2debian-pulseaudio but it is not installable
The following actions will resolve these dependencies:

Remove the following packages:
ubuntu-desktop

Leave the following dependencies unresolved:
catfish recommends slocate
Score is -81

Accept this solution? [Y/n/q/?]

这几行最让我担心：

Remove the following packages:
ubuntu-desktop

有没有办法在 Gnome 旁边安装 XFCE 桌面而不会导致 ubuntu-desktop 崩溃？

更多信息 (1)

apt-get在同一问题中使用结果。

更多信息 (2)

附件是 aptitude 提供的其他解决方案：

上面列出了解决方案 1。

解决方案 2：以下操作将解决这些依赖关系：

Keep the following packages at their current version:
libsdl1.2debian-alsa [Not Installed]
libsdl1.2debian-pulseaudio [1.2.14-4ubuntu1.1 (lucid-updates, now)]

Leave the following dependencies unresolved:
catfish recommends slocate
xubuntu-desktop recommends libsdl1.2debian-alsa
Score is -210

Accept this solution? [Y/n/q/?] 

解决方案3：

The following actions will resolve these dependencies:

Keep the following packages at their current version:
libsdl1.2debian-alsa [Not Installed]

Downgrade the following packages:
libsdl1.2debian [1.2.14-4ubuntu1.1 (lucid-updates, now) -> 1.2.14-4ubuntu1 (lucid)]
libsdl1.2debian-pulseaudio [1.2.14-4ubuntu1.1 (lucid-updates, now) -> 1.2.14-4ubuntu1 (lucid)]

Leave the following dependencies unresolved:
catfish recommends slocate
xubuntu-desktop recommends libsdl1.2debian-alsa
Score is -220

Accept this solution? [Y/n/q/?]