[Feisty] xfce4 synced, but not dependencies

Binary package hint: xfce4

aptitude install output:
toby@leopard:~/src/asoundconf-gtk$ sudo aptitude install xfce4
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading extended state information
Initialising package states... Done
Writing extended state information... Done
Building tag database... Done
The following packages are BROKEN:
  xfce4
The following NEW packages will be automatically installed:
  gtk2-engines-xfce
The following NEW packages will be installed:
  gtk2-engines-xfce
0 packages upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
Need to get 44.4kB of archives. After unpacking 479kB will be used.
The following packages have unmet dependencies:
  xfce4: Depends: xfwm4-themes (>= 4.3.99.1-1) but 4.3.90.2-0ubuntu1 is installed.
         Depends: xfce4-icon-theme (>= 4.3.99.1-1) but 4.3.90.2-0ubuntu1 is installed.
         Depends: xfce4-session (>= 4.3.99.1-1) but 4.3.90.2svn+r22852-0ubuntu5 is installed.

apt-cache policy:
toby@leopard:~/src/asoundconf-gtk$ apt-cache policy xfce4 xfce4-session
xfce4:
  Installed: (none)
  Candidate: 4.3.99.1
  Version table:
     4.3.99.1 0
        500 http://gb.archive.ubuntu.com feisty/universe Packages
     4.3.90.2 0
        100 /var/lib/dpkg/status
xfce4-session:
  Installed: 4.3.90.2svn+r22852-0ubuntu5
  Candidate: 4.3.90.2svn+r22852-0ubuntu5
  Version table:
 *** 4.3.90.2svn+r22852-0ubuntu5 0
        500 http://gb.archive.ubuntu.com feisty/main Packages
        100 /var/lib/dpkg/status

It seems xfce4 has been synced, but not its dependencies.