Extreme display corruption

[Nikos Chantziaras]

Something in my system makes KDevelop unable to display anything, and 
when it does, widgets are simply flashing for a bit and then gone again. 
  I've tried versions from 3.9.93 to latest SVN.

Basically, it looks like this:

   http://imagebin.ca/view/3jS9RoVj.html

During start-up, KDevelop spits these out:

   WARNING: deleting stale lockfile /home/realnc/.kdevduchain/0/lock
   <unknown program name>(19490)/ KDevelop::allocateRepository:
   picked duchain directory "/home/realnc/.kdevduchain/0"
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.
   QSqlDatabasePrivate::removeDatabase: connection 'GetNamespaceName-
   35882640-2' is still in use, all queries will cease to work.
   QSqlDatabasePrivate::removeDatabase: connection 'GetNamespaceName-
   35882640-10' is still in use, all queries will cease to work.
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.
   Calling appendChild() on a null node does nothing.

And then after loading, if I move the mouse and widgets start flashing 
in and out, tons of the following are shown:

   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x380d5780
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x380d5780
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x380d5780
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x380d5780
   QNativeImage: Unable to attach to shared memory segment.
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x3293020
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x3293020
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x3293020
   QNativeImage: Unable to attach to shared memory segment.
   X Error: BadDrawable (invalid Pixmap or Window parameter) 9
     Major opcode: 62 (X_CopyArea)
     Resource id:  0x0
   QNativeImage: Unable to attach to shared memory segment.

etc, etc, ad infinitum.

Any hints on how to track this down?  No other application (KDE or not) 
has this problem.