hi,
the lxde package is brocken in your backports:
########################################################
aptitude -t lenny-backports install lxde
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
The following packages are BROKEN:
lxde
The following NEW packages will be installed:
lxinput{a}
1 packages upgraded, 1 newly installed, 0 to remove and 27 not upgraded.
Need to get 43,1kB of archives. After unpacking 602kB will be used.
The following packages have unmet dependencies:
lxde: Depends: lxmusic which is a virtual package.
The following actions will resolve these dependencies:
Keep the following packages at their current version:
lxde [0.3.2.1+svn20080509-5 (stable, now)]
Score is -9880
Accept this solution? [Y/n/q/?] n
The following actions will resolve these dependencies:
Remove the following packages:
lxde
Score is -9881
Accept this solution? [Y/n/q/?] n
*** No more solutions available ***########################################################
but other package like pidgin and iceweasel or nm-applet worked very fine.
best regards
Sia