Here is some more debugging information from gdb i got.

$ gdb mousepad 2>&1 | tee /tmp/gdb-mousepad-open.txt
GNU gdb 6.6-debian
Copyright (C) 2006 Free Software Foundation, Inc.
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Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i486-linux-gnu"...
Using host libthread_db library "/lib/tls/i686/cmov/libthread_db.so.1".
(gdb) handle SIG33 pass nostop noprint
Signal        Stop      Print   Pass to program Description
SIG33         No        No      Yes             Real-time event 33
(gdb) set pagination 0
(gdb) run
Starting program: /usr/bin/mousepad 
Failed to read a valid object file image from memory.
[Thread debugging using libthread_db enabled]
[New Thread -1218402624 (LWP 25632)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1218402624 (LWP 25632)]
0xb7b7ad5f in IA__gdk_drawable_get_screen (drawable=0x4c4c) at gdkdraw.c:202
202     gdkdraw.c: No such file or directory.
        in gdkdraw.c
(gdb) backtrace 
#0  0xb7b7ad5f in IA__gdk_drawable_get_screen (drawable=0x4c4c) at gdkdraw.c:202
#1  0xb7bbe178 in IA__gdk_window_new (parent=0x4c4c, attributes=0xbfa824c4, attributes_mask=108) at gdkwindow-x11.c:673
#2  0xb7dedeef in text_window_realize (win=0x80f2c40, widget=0x8078f88) at gtktextview.c:7478
#3  0xb7dee1a3 in set_window_width (text_view=0x80ba018, width=<value optimized out>, type=GTK_TEXT_WINDOW_LEFT, winp=0x80ba098) at gtktextview.c:8129
#4  0x08053914 in show_line_numbers (text_view=0x80ba018, visible=1) at linenum.c:287
#5  0xb7d1bf58 in gtk_item_factory_callback_marshal (widget=0x60001, func_data=0x8078f88) at gtkitemfactory.c:188
#6  0xb78489b9 in g_cclosure_marshal_VOID__VOID () from /usr/lib/libgobject-2.0.so.0
#7  0xb783b62b in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#8  0xb784c0e3 in ?? () from /usr/lib/libgobject-2.0.so.0
#9  0x080b02f8 in ?? ()
#10 0x00000000 in ?? ()
(gdb) info registers 
eax            0x80772f0        134705904
ecx            0x60001  393217
edx            0x8078f88        134713224
ebx            0xb7be623c       -1212259780
esp            0xbfa823e0       0xbfa823e0
ebp            0xbfa823f8       0xbfa823f8
esi            0x4c4c   19532
edi            0x80f2c40        135212096
eip            0xb7b7ad5f       0xb7b7ad5f <IA__gdk_drawable_get_screen+31>
eflags         0x210202 [ IF RF ID ]
cs             0x73     115
ss             0x7b     123
ds             0x7b     123
es             0x7b     123
fs             0x0      0
gs             0x33     51
(gdb) thread apply all backtrace

Thread 1 (Thread -1218402624 (LWP 25632)):
#0  0xb7b7ad5f in IA__gdk_drawable_get_screen (drawable=0x4c4c) at gdkdraw.c:202
#1  0xb7bbe178 in IA__gdk_window_new (parent=0x4c4c, attributes=0xbfa824c4, attributes_mask=108) at gdkwindow-x11.c:673
#2  0xb7dedeef in text_window_realize (win=0x80f2c40, widget=0x8078f88) at gtktextview.c:7478
#3  0xb7dee1a3 in set_window_width (text_view=0x80ba018, width=<value optimized out>, type=GTK_TEXT_WINDOW_LEFT, winp=0x80ba098) at gtktextview.c:8129
#4  0x08053914 in show_line_numbers (text_view=0x80ba018, visible=1) at linenum.c:287
#5  0xb7d1bf58 in gtk_item_factory_callback_marshal (widget=0x60001, func_data=0x8078f88) at gtkitemfactory.c:188
#6  0xb78489b9 in g_cclosure_marshal_VOID__VOID () from /usr/lib/libgobject-2.0.so.0
#7  0xb783b62b in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#8  0xb784c0e3 in ?? () from /usr/lib/libgobject-2.0.so.0
#9  0x080b02f8 in ?? ()
#10 0x00000000 in ?? ()
(gdb) auit
Undefined command: "auit".  Try "help".
(gdb) quit

I have tried to get some information from mousepad through gdb when I run it as root and try to hit the "open file" option.  It doesn't work because the program isn't segfaulting, it is just hanging almost as if i sent the process to the background with ctrl+z  but gdb just says continuing if I try to do anything with it.  

I hope I have provided all the debugging info needed.  I can't see how I can provide anymore I have all the debugging symbols requested installed and I followed the instructions for backtracing exactly.  I have included the valgrind logs of various reproduction methods.  Can someone else just confirm this is a bug, by trying to run sudo mousepad and trying to open something.  Or apt-get install mousepad  and just see if mousepad segfaults when you try to open it.   Also try running gedit with sudo as well, and try clicking the open button.  Should hang the app.  Shouldn't take much work for someone to confirm this, and when someone does I have more than enough debugging info included on this bug report.

Thanks