In obconf.glad there are several instances of <property name="adjustment">0 0 10000 10 10 10</property>. From what I know this is because the file was created with an obsolete version of glad that is now deprecated. The result are lots of errors in .xsession-errors. The fix is easy, just change the last value from 10 to 0. More information: http://library.gnome.org/devel/gtk/unstable/GtkAdjustment.html#gtk-adjustment-configure http://library.gnome.org/devel/gtk/unstable/GtkAdjustment.html#GtkAdjustment--page-size Original bug report: http://bugs.debian.org/615102