Here's a hopefully useful stack trace:

GNU gdb 6.8-debian
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu"...
(gdb) run
Starting program: /usr/bin/python /usr/lib/deskbar-applet/deskbar-applet -d
[Thread debugging using libthread_db enabled]
[New Thread 0x7f4eac4076f0 (LWP 5237)]
04-09 11:10:36 root         INFO     Starting Deskbar instance: <gnome.applet.Applet object at 0x25411e0 (PanelApplet at 0x25b0000)> OAFIID:Deskbar_Applet
04-09 11:10:36 deskbar.core.Keybinder INFO     Binding Global shortcut <Alt>F3 to focus the deskbar
04-09 11:10:36 deskbar.core.CoreImpl INFO     Successfully binded Deskbar to <Alt>F3
04-09 11:10:36 deskbar.core.ModuleLoader WARNING  Class EpiphanyBookmarksHandler in file /usr/lib/deskbar-applet/modules-2.20-compatible/epiphany.py has missing requirements. Skipping.
04-09 11:10:36 deskbar.core.ModuleLoader WARNING  Class EpiphanyHistoryHandler in file /usr/lib/deskbar-applet/modules-2.20-compatible/epiphany.py has missing requirements. Skipping.
04-09 11:10:36 deskbar.core.ModuleLoader WARNING  Class EpiphanySearchHandler in file /usr/lib/deskbar-applet/modules-2.20-compatible/epiphany.py has missing requirements. Skipping.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Programs' from file /usr/lib/deskbar-applet/modules-2.20-compatible/programs.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Dictionary' from file /usr/lib/deskbar-applet/modules-2.20-compatible/programs.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Files and Folders Search' from file /usr/lib/deskbar-applet/modules-2.20-compatible/programs.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Developer Documentation' from file /usr/lib/deskbar-applet/modules-2.20-compatible/programs.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Tomboy Notes' from file /usr/lib/deskbar-applet/modules-2.20-compatible/tomboy.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Web' from file /usr/lib/deskbar-applet/modules-2.20-compatible/web_address.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'OpenSearch' from file /usr/lib/deskbar-applet/modules-2.20-compatible/opensearch.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Calculator' from file /usr/lib/deskbar-applet/modules-2.20-compatible/calculator.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'del.icio.us Bookmarks' from file /usr/lib/deskbar-applet/modules-2.20-compatible/desklicious.py.
04-09 11:10:36 deskbar.core.ModuleLoader INFO     Loading module 'Computer Actions' from file /usr/lib/deskbar-applet/modules-2.20-compatible/gdmactions.py.

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7f4eac4076f0 (LWP 5237)]
PyType_IsSubtype (a=0xfffffffffffffffd, b=0x7f4eaa26e6a0) at ../Objects/typeobject.c:1157
1157	../Objects/typeobject.c: No such file or directory.
	in ../Objects/typeobject.c
(gdb) bt
#0  PyType_IsSubtype (a=0xfffffffffffffffd, b=0x7f4eaa26e6a0) at ../Objects/typeobject.c:1157
#1  0x00007f4eaa0599fc in pyg_type_add_interfaces (class=0x292d530, instance_type=42386864, bases=0x28ea5a8, new_interfaces=0, parent_interfaces=0x288c7e0, n_parent_interfaces=0)
    at /build/buildd/pygobject-2.16.1/gobject/gobjectmodule.c:1088
#2  0x00007f4eaa059d23 in pyg_type_register (class=0x292d530, type_name=<value optimized out>) at /build/buildd/pygobject-2.16.1/gobject/gobjectmodule.c:1237
#3  0x00007f4eaa05ab78 in _wrap_pyg_type_register (self=<value optimized out>, args=<value optimized out>) at /build/buildd/pygobject-2.16.1/gobject/gobjectmodule.c:954
#4  0x00000000004a2b03 in PyEval_EvalFrameEx (f=0x1b8e9c0, throwflag=<value optimized out>) at ../Python/ceval.c:3706
#5  0x00000000004a3dae in PyEval_EvalFrameEx (f=0x1b281c0, throwflag=<value optimized out>) at ../Python/ceval.c:3792
#6  0x00000000004a4649 in PyEval_EvalCodeEx (co=0x7f4eac327468, globals=<value optimized out>, locals=<value optimized out>, args=0x28d1590, argcount=4, kws=0x0, kwcount=0, defs=0x0, defcount=0, 
    closure=0x0) at ../Python/ceval.c:2968
#7  0x00000000005329ad in function_call (func=0x7f4eac2676e0, arg=0x28d1578, kw=0x0) at ../Objects/funcobject.c:524
#8  0x000000000041d3bd in PyObject_Call (func=0x7f4eac2676e0, arg=0x28d1578, kw=0x0) at ../Objects/abstract.c:2492
#9  0x0000000000424f48 in instancemethod_call (func=0x7f4eac2676e0, arg=0x28d1578, kw=0x0) at ../Objects/classobject.c:2579
#10 0x000000000041d3bd in PyObject_Call (func=0x27cb9b0, arg=0x28bd9b0, kw=0x0) at ../Objects/abstract.c:2492
#11 0x000000000047413c in slot_tp_init (self=0x292d530, args=0x28bd9b0, kwds=0x0) at ../Objects/typeobject.c:5632
#12 0x000000000046bd3b in type_call (type=0x1aeebf0, args=0x28bd9b0, kwds=0x0) at ../Objects/typeobject.c:745
#13 0x00000000004226b8 in PyObject_CallFunctionObjArgs (callable=0x1aeebf0) at ../Objects/abstract.c:2492
#14 0x00000000004269dc in PyClass_New (bases=0x28ea5a8, dict=0x292afa0, name=0x28b5768) at ../Objects/classobject.c:92
#15 0x0000000000426bc8 in class_new (type=<value optimized out>, args=<value optimized out>, kwds=<value optimized out>) at ../Objects/classobject.c:182
#16 0x000000000046bc03 in type_call (type=0x1fc77d0, args=0x28bd960, kwds=0x0) at ../Objects/typeobject.c:731
#17 0x00000000004226b8 in PyObject_CallFunctionObjArgs (callable=0x816bc0) at ../Objects/abstract.c:2492
#18 0x000000000049ee67 in PyEval_EvalFrameEx (f=0x28e0b10, throwflag=<value optimized out>) at ../Python/ceval.c:4303
#19 0x00000000004a4649 in PyEval_EvalCodeEx (co=0x28cf288, globals=<value optimized out>, locals=<value optimized out>, args=0x0, argcount=0, kws=0x0, kwcount=0, defs=0x0, defcount=0, closure=0x0)
    at ../Python/ceval.c:2968
#20 0x00000000004a4762 in PyEval_EvalCode (co=0x1fc77d0, globals=0x7f4eaa26e6a0, locals=0x0) at ../Python/ceval.c:522
#21 0x00000000004b832e in PyImport_ExecCodeModuleEx (name=0x7fffb4423ad0 "deskbar.core.Web", co=0x28cf288, pathname=0x7fffb4421990 "/usr/lib/python2.6/dist-packages/deskbar/core/Web.pyc")
    at ../Python/import.c:680
#22 0x00000000004b9461 in load_source_module (name=0x7fffb4423ad0 "deskbar.core.Web", pathname=0x7fffb4421990 "/usr/lib/python2.6/dist-packages/deskbar/core/Web.pyc", fp=<value optimized out>)
    at ../Python/import.c:1016
#23 0x00000000004ba2ba in import_submodule (mod=0x1eee7c0, subname=0x7fffb4423add "Web", fullname=0x7fffb4423ad0 "deskbar.core.Web") at ../Python/import.c:2590
#24 0x00000000004ba54c in load_next (mod=0x1eee7c0, altmod=0x1eee7c0, p_name=<value optimized out>, buf=0x7fffb4423ad0 "deskbar.core.Web", p_buflen=0x7fffb4423ac8) at ../Python/import.c:2410
#25 0x00000000004babfe in import_module_level (name=0x0, globals=<value optimized out>, locals=<value optimized out>, fromlist=0x28a4d60, level=32434112) at ../Python/import.c:2139
#26 0x00000000004bb19f in PyImport_ImportModuleLevel (name=0x28bfefc "deskbar.core.Web", globals=0x28df8f0, locals=0x28df8f0, fromlist=0x28a4d60, level=-1) at ../Python/import.c:2183
#27 0x000000000049c869 in builtin___import__ (self=<value optimized out>, args=<value optimized out>, kwds=<value optimized out>) at ../Python/bltinmodule.c:48
#28 0x000000000041d3bd in PyObject_Call (func=0x7f4eac3d8050, arg=0x28ba3c0, kw=0x0) at ../Objects/abstract.c:2492
#29 0x000000000049cd46 in PyEval_CallObjectWithKeywords (func=0x7f4eac3d8050, arg=0x28ba3c0, kw=0x0) at ../Python/ceval.c:3575
#30 0x000000000049faa2 in PyEval_EvalFrameEx (f=0x28dfd00, throwflag=<value optimized out>) at ../Python/ceval.c:2136
#31 0x00000000004a4649 in PyEval_EvalCodeEx (co=0x28c93f0, globals=<value optimized out>, locals=<value optimized out>, args=0x0, argcount=0, kws=0x0, kwcount=0, defs=0x0, defcount=0, closure=0x0)
    at ../Python/ceval.c:2968
#32 0x00000000004a4762 in PyEval_EvalCode (co=0x1fc77d0, globals=0x7f4eaa26e6a0, locals=0x0) at ../Python/ceval.c:522
#33 0x00000000004b832e in PyImport_ExecCodeModuleEx (name=0x28314a4 "twitter", co=0x28c93f0, pathname=0x7fffb4425100 "/usr/lib/deskbar-applet/modules-2.20-compatible/twitter.pyc")
    at ../Python/import.c:680
#34 0x00000000004b9461 in load_source_module (name=0x28314a4 "twitter", pathname=0x7fffb4425100 "/usr/lib/deskbar-applet/modules-2.20-compatible/twitter.pyc", fp=<value optimized out>)
    at ../Python/import.c:1016
#35 0x00000000004bb999 in imp_load_module (self=<value optimized out>, args=<value optimized out>) at ../Python/import.c:3059
#36 0x00000000004a2b03 in PyEval_EvalFrameEx (f=0x27a9e40, throwflag=<value optimized out>) at ../Python/ceval.c:3706
#37 0x00000000004a3dae in PyEval_EvalFrameEx (f=0x27a9c00, throwflag=<value optimized out>) at ../Python/ceval.c:3792
#38 0x00000000004a3dae in PyEval_EvalFrameEx (f=0x27a9a00, throwflag=<value optimized out>) at ../Python/ceval.c:3792
#39 0x00000000004a3dae in PyEval_EvalFrameEx (f=0x27a9820, throwflag=<value optimized out>) at ../Python/ceval.c:3792
#40 0x00000000004a4649 in PyEval_EvalCodeEx (co=0x2070198, globals=<value optimized out>, locals=<value optimized out>, args=0x2545668, argcount=1, kws=0x0, kwcount=0, defs=0x0, defcount=0, 
    closure=0x0) at ../Python/ceval.c:2968
#41 0x00000000005329ad in function_call (func=0x23736e0, arg=0x2545650, kw=0x0) at ../Objects/funcobject.c:524
#42 0x000000000041d3bd in PyObject_Call (func=0x23736e0, arg=0x2545650, kw=0x0) at ../Objects/abstract.c:2492
#43 0x0000000000424f48 in instancemethod_call (func=0x23736e0, arg=0x2545650, kw=0x0) at ../Objects/classobject.c:2579
#44 0x000000000041d3bd in PyObject_Call (func=0x25596e0, arg=0x7f4eac3c7050, kw=0x0) at ../Objects/abstract.c:2492
#45 0x000000000049cd46 in PyEval_CallObjectWithKeywords (func=0x25596e0, arg=0x7f4eac3c7050, kw=0x0) at ../Python/ceval.c:3575
#46 0x00007f4eaa6ab35c in _pyglib_handler_marshal (user_data=0x253e440) at /build/buildd/pygobject-2.16.1/glib/pyglib.c:562
#47 0x00007f4eaa8e80ca in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#48 0x00007f4eaa8eb7a0 in ?? () from /usr/lib/libglib-2.0.so.0
#49 0x00007f4eaa8ebc6d in g_main_loop_run () from /usr/lib/libglib-2.0.so.0
#50 0x00007f4ea1e78796 in bonobo_main () from /usr/lib/libbonobo-2.so.0
#51 0x00007f4ea1e76b51 in bonobo_generic_factory_main_timeout () from /usr/lib/libbonobo-2.so.0
#52 0x00007f4ea32b5e11 in panel_applet_factory_main_closure () from /usr/lib/libpanel-applet-2.so.0
#53 0x00007f4ea34c1464 in ?? () from /var/lib/python-support/python2.6/gtk-2.0/gnomeapplet.so
#54 0x00000000004a2b03 in PyEval_EvalFrameEx (f=0x1a6a330, throwflag=<value optimized out>) at ../Python/ceval.c:3706
#55 0x00000000004a4649 in PyEval_EvalCodeEx (co=0x7f4eac31d8a0, globals=<value optimized out>, locals=<value optimized out>, args=0x0, argcount=0, kws=0x0, kwcount=0, defs=0x0, defcount=0, closure=0x0)
    at ../Python/ceval.c:2968
#56 0x00000000004a4762 in PyEval_EvalCode (co=0x1fc77d0, globals=0x7f4eaa26e6a0, locals=0x0) at ../Python/ceval.c:522
#57 0x00000000004c4c3c in PyRun_FileExFlags (fp=0x1a558a0, filename=0x7fffb4429a3e "/usr/lib/deskbar-applet/deskbar-applet", start=<value optimized out>, globals=0x19fc750, locals=0x19fc750, 
    closeit=1, flags=0x7fffb4427a90) at ../Python/pythonrun.c:1335
#58 0x00000000004c4f6b in PyRun_SimpleFileExFlags (fp=0x1a558a0, filename=0x7fffb4429a3e "/usr/lib/deskbar-applet/deskbar-applet", closeit=1, flags=0x7fffb4427a90) at ../Python/pythonrun.c:931
#59 0x00000000004189ce in Py_Main (argc=<value optimized out>, argv=0x7fffb4427ba8) at ../Modules/main.c:599
#60 0x00007f4eab3f65a6 in __libc_start_main (main=0x417bb0 <main>, argc=3, ubp_av=0x7fffb4427ba8, init=0x54a180 <__libc_csu_init>, fini=<value optimized out>, rtld_fini=<value optimized out>, 
    stack_end=0x7fffb4427b98) at libc-start.c:220
#61 0x0000000000417ae9 in _start () at ../sysdeps/x86_64/elf/start.S:113