Comment 2 for bug 34518

I have the exact same issue, and I can confirm that changing my theme to anything but Human works just fine, no crashes.

I have updated just now, and there were no newer updates for the gtk2-engines-ubuntulooks package. My version is 0.9.5-1.

(gdb) bt
#0 0x770dcd1a in strcmp () from /lib/tls/i686/cmov/libc.so.6
#1 0x774275d4 in g_str_equal () from /usr/lib/libglib-2.0.so.0
#2 0x767db8f0 in ubuntulooks_rc_style_register_type ()
   from /usr/lib/gtk-2.0/2.4.0/engines/libubuntulooks.so
#3 0x767dba08 in ubuntulooks_rc_style_register_type ()
   from /usr/lib/gtk-2.0/2.4.0/engines/libubuntulooks.so
#4 0x77864ece in gtk_paint_shadow () from /usr/lib/libgtk-x11-2.0.so.0
#5 0x77ee3883 in e_calendar_item_get_type ()
   from /usr/lib/evolution/2.6/libemiscwidgets.so.0
#6 0x77a156a4 in gnome_canvas_item_move () from /usr/lib/libgnomecanvas-2.so.0
#7 0x77a1adc5 in gnome_canvas_item_new () from /usr/lib/libgnomecanvas-2.so.0
#8 0x7780a540 in _gtk_marshal_BOOLEAN__BOXED ()
   from /usr/lib/libgtk-x11-2.0.so.0
#9 0x7747b16f in g_cclosure_new_swap () from /usr/lib/libgobject-2.0.so.0
#10 0x7747b79f in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#11 0x7748a9ce in g_signal_stop_emission () from /usr/lib/libgobject-2.0.so.0
#12 0x7748b886 in g_signal_emit_valist () from /usr/lib/libgobject-2.0.so.0
#13 0x7748be89 in g_signal_emit () from /usr/lib/libgobject-2.0.so.0
#14 0x778ec71f in gtk_widget_activate () from /usr/lib/libgtk-x11-2.0.so.0
#15 0x77a1788f in gnome_canvas_item_grab_focus ()
   from /usr/lib/libgnomecanvas-2.so.0
#16 0x77a179bf in gnome_canvas_item_grab_focus ()
   from /usr/lib/libgnomecanvas-2.so.0
#17 0x7740faf2 in g_child_watch_add () from /usr/lib/libglib-2.0.so.0
---Type <return> to continue, or q <return> to quit---
#18 0x7740d7d7 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#19 0x77410896 in g_main_context_check () from /usr/lib/libglib-2.0.so.0
#20 0x77410bb8 in g_main_loop_run () from /usr/lib/libglib-2.0.so.0
#21 0x77b3a477 in bonobo_main () from /usr/lib/libbonobo-2.so.0
#22 0x0806221b in main ()