Bug#647722: kdm: Stuck on the splash screen when kde has compositing enabled

[Joan <aseques@gmail.com>]

Package: kdm
Version: 4:4.6.5-3
Severity: important

Dear Maintainer,

I'm running a fully updated wheezy system, from some point I can't see the desktop after the splash screen.
With some help from the guys on irc, we noticed that the problem is with compositing. I can work with my desktop
either doing the Alt + Shift + F12 or changign the kwinrc value for Compositing to false.
I've tried to boot the system with the latest nvidia package from unstable (290.06-1) with the same results.
I also tried with different users and creating the profile from scratch.

-- System Information:
Debian Release: wheezy/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (250, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 3.0.0-1-686-pae (SMP w/1 CPU core)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

Versions of packages kdm depends on:
ii  adduser                           3.113       
ii  consolekit                        0.4.5-1     
ii  debconf [debconf-2.0]             1.5.40      
ii  kdebase-runtime                   4:4.6.5-1+b1
ii  kdebase-workspace-kgreet-plugins  4:4.6.5-3   
ii  libc6                             2.13-21     
ii  libck-connector0                  0.4.5-1     
ii  libdbus-1-3                       1.4.16-1    
ii  libkdecore5                       4:4.6.5-2+b1
ii  libkdeui5                         4:4.6.5-2+b1
ii  libkio5                           4:4.6.5-2+b1
ii  libknewstuff3-4                   4:4.6.5-2+b1
ii  libkworkspace4                    4:4.6.5-3   
ii  libpam0g                          1.1.3-4     
ii  libqimageblitz4                   1:0.0.6-4   
ii  libqt4-svg                        4:4.7.3-5   
ii  libqt4-xml                        4:4.7.3-5   
ii  libqtcore4                        4:4.7.3-5   
ii  libqtgui4                         4:4.7.3-5   
ii  libstdc++6                        4.6.1-15    
ii  libx11-6                          2:1.4.4-2   
ii  libxau6                           1:1.0.6-3   
ii  libxdmcp6                         1:1.1.0-3   
ii  libxtst6                          2:1.2.0-4   
ii  lsb-base                          3.2-28      

Versions of packages kdm recommends:
ii  kde-window-manager [x-window-manager]  4:4.6.5-3     
ii  kdebase                                5:66          
ii  konsole [x-terminal-emulator]          4:4.6.5-1     
ii  logrotate                              3.7.8-6       
ii  tightvncserver [xserver]               1.3.9-6.2     
ii  xfce4-session [x-session-manager]      4.8.2-1       
ii  xfwm4 [x-window-manager]               4.8.2-1       
ii  xserver-xephyr [xserver]               2:1.11.1.901-2
ii  xserver-xorg [xserver]                 1:7.6+9       
ii  xterm [x-terminal-emulator]            276-1         

Versions of packages kdm suggests:
ii  kdepasswd  4:4.6.5-1

-- debconf information:
  kdm/stop_running_server_with_children: false
* shared/default-x-display-manager: kdm
  kdm/daemon_name: /usr/bin/kdm