Description of problem:
dia segfaults when editing the properties of a clock object

Version-Release number of selected component (if applicable):
dia-0.96.1-13.fc11.x86_64

How reproducible:
always

Steps to Reproduce:
1. launch dia
2. select misc in the toolbox dropdown box
3. select the clock object
4. left-click on canvas to add a clock object
5. right click on the clock object in canvas and select properties
  
Actual results:
SIGSEGV. Backtrace :

Program received signal SIGSEGV, Segmentation fault.
0x0000003647656158 in prop_dialog_container_pop (dialog=0x7f8929814f10) at propdialogs.c:163
163	  dialog->lastcont = g_ptr_array_index(dialog->containers,
(gdb) bt full
#0  0x0000003647656158 in prop_dialog_container_pop (dialog=0x7f8929814f10) at propdialogs.c:163
No locals.
#1  0x00000036476551bc in notebook_endprop_get_widget (prop=<value optimized out>, dialog=0x0) at prop_widgets.c:334
No locals.
#2  0x000000364765062b in commonprop_get_widget (prop=0x0, dialog=0x0) at prop_basic.c:123
        wid = 0x7f892981fd50
#3  0x0000003647656395 in prop_dialog_add_property (dialog=0x7f8929814f10, prop=0x7f892971ff80) at propdialogs.c:254
        widget = <value optimized out>
        pwa = {prop = 0x7f8929709d30, widget = 0x7f8929820b90}
        label = <value optimized out>
#4  0x00000036476567b5 in prop_dialog_add_properties (props=<value optimized out>, dialog=<value optimized out>) at propdialogs.c:277
        i = 10
#5  prop_dialog_fill (is_default=<value optimized out>, obj=<value optimized out>, dialog=<value optimized out>) at propdialogs.c:321
        pdesc = <value optimized out>
        props = 0x7f8929711380
#6  prop_dialog_new (obj=0x7f8929869790, is_default=0) at propdialogs.c:61
No locals.
#7  0x000000364764fef9 in object_create_props_dialog (obj=0x0, is_default=0) at propobject.c:150
No locals.
#8  0x0000000000420eb8 in properties_show (dia=0x7f89297fba10, obj=0x7f8929869790) at properties.c:188
        properties = 0x0


Expected results:
Clock properties box should come up