I'm not sure if this happened while I was degragmenting my HD or if it happened during a virus scan (using ClamAV). Here's the crash report:
---
Crash log created on 25/06/2006 at 14:22:01.

version = 1.8.3
compile date = May 13 2006
compile time = 00:15:53
features = DISTRIBUTION EXERCISES GNET GNET2 GTK_MULTIHEAD 


code = c0000005
flags = 0
address = 555910
params = 2
C:\Program Files\Workrave\lib\Workrave.exe caused an Access Violation at location 00555910 writing to location 00534f7c

Registers:

eax=00534f7c ebx=00ce6cbc ecx=7ffdd000 edx=0022f0c4 esi=0022f1e0 edi=0022f1e0
eip=00555910 esp=0022f0ac ebp=0022f0e8 iopl=0         nv up ei pl nz na pe nc
cs=001b  ss=0023  ds=0023  es=0023  fs=003b  gs=0000             efl=00010202

Stack trace:

PC        Frame     Ret
00555910  0022F0E8  005460B3
005460B3  0022F118  0054623E
0054623E  0022F148  00534ED9
00534ED9  0022F178  00453987
00453987  0022F198  00413191
00413191  0022F24C  0044FC65
0044FC65  0022F27C  00ACDB51
00ACDB51  0022F2AC  008A370B
008A370B  0022F2DC  008A34DE
008A34DE  0022F31C  008B6BBB
008B6BBB  0022F56C  008B5494
008B5494  0022F81C  008B5676
008B5676  0022F83C  00BBAFB5
00BBAFB5  0022F86C  00BBAD45
00BBAD45  0022F88C  00ACB35E
00ACB35E  0022F8CC  008F8848
008F8848  0022F97C  008F8948
008F8948  0022F99C  008F8655
008F8655  0022F9AC  0074A176
0074A176  0022F9CC  00748267
00748267  0022FA0C  00748D60
00748D60  0022FA1C  00749007
00749007  0022FA4C  007494AA
007494AA  0022FA7C  00ACACFF
00ACACFF  0022FA9C  0046A6A7
0046A6A7  0022FAAC  0046A4E6
0046A4E6  0022FABC  00402D63
00402D63  0022FAE0  0041EFEA
0041EFEA  0022FAF4  0041F040
0041F040  0022FEF8  0055C8EA
0055C8EA  0022FF78  004011E7
004011E7  0022FFB0  00401258
00401258  0022FFC0  7C816D4F
7C816D4F  0022FFF0  00000000

Registry dump:

key = Software\Workrave

key = Software\Workrave\distribution
  value = port
  string data = 27273
  value = reconnect_attempts
  string data = 5
  value = reconnect_interval
  string data = 15

key = Software\Workrave\gui

key = Software\Workrave\gui\applet
  value = cycle_time
  string data = 10

key = Software\Workrave\gui\breaks
  value = block_mode
  string data = 0

key = Software\Workrave\gui\breaks\daily_limit
  value = max_preludes
  string data = 3
  value = max_postpone
  string data = -1
  value = ignorable_break
  string data = 1
  value = enabled
  string data = 1
  value = exercises
  string data = 0

key = Software\Workrave\gui\breaks\micro_pause
  value = max_preludes
  string data = 3
  value = max_postpone
  string data = -1
  value = ignorable_break
  string data = 1
  value = enabled
  string data = 1
  value = exercises
  string data = 0

key = Software\Workrave\gui\breaks\rest_break
  value = max_preludes
  string data = 3
  value = max_postpone
  string data = -1
  value = ignorable_break
  string data = 1
  value = enabled
  string data = 1
  value = exercises
  string data = 3

key = Software\Workrave\gui\main_window
  value = x
  string data = 256
  value = y
  string data = 256
  value = head
  string data = 0
  value = cycle_time
  string data = 10

key = Software\Workrave\timers

key = Software\Workrave\timers\daily_limit
  value = limit
  string data = 28800
  value = auto_reset
  string data = 0
  value = reset_pred
  string data = day/4:00
  value = snooze
  string data = 3600
  value = activity_sensitive
  string data = 1

key = Software\Workrave\timers\micro_pause
  value = limit
  string data = 900
  value = auto_reset
  string data = 30
  value = reset_pred
  string data = 
  value = snooze
  string data = 900
  value = activity_sensitive
  string data = 1

key = Software\Workrave\timers\rest_break
  value = limit
  string data = 3600
  value = auto_reset
  string data = 420
  value = reset_pred
  string data = 
  value = snooze
  string data = 900
  value = activity_sensitive
  string data = 1

PC        Frame     Ret
00555910  0022F0E8  005460B3 new
005460B3  0022F118  0054623E create_new_wrapper(_GObject*)
0054623E  0022F148  00534ED9 Glib::wrap_auto(_GObject*, bool)
00534ED9  0022F178  00453987 Glib::wrap(_PangoLayout*, bool)
00453987  0022F198  00413191 Gtk::Widget::create_pango_layout(Glib::ustring const&)
00413191  0022F24C  0044FC65 TimeBar::on_expose_event(_GdkEventExpose*)

I received similar crash reports in the 1.8.5 series of Workrave. I haven't received any reports since 1.9.0. So I'm closing this bug.

Please reopen if  you still see this bug with a more recent version of Workrave.