[racket-dev] drracket crash with bad prefs

Occasionally, my prefs file gets into a state where drracket cant
start and fails with this error:

-: expects type <number> as 2nd argument, given: #f; other arguments were: 76

 === context ===
C:\plt\collects\framework\private\frame.rkt:255:2
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\drracket\private\frame.rkt:594:4
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\drracket\private\unit.rkt:1301:4
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\drracket\private\module-language.rkt:816:4
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\drracket\private\debug.rkt:1520:4
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\drracket\private\module-language-tools.rkt:50:4
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
C:\plt\collects\drracket\private\syncheck\gui.rkt:1404:6
C:\plt\collects\racket\private\class-internal.rkt:3680:0: continue-make-super
...



If I wipe away the following line in the prefs file, it starts fine.

(plt:framework-pref:drracket:unit-window-position (1 76 9))


But I dont know what I did to get that line to appear in my prefs.
Last few things I did was run a slideshow presentation and activated a
few lazy stepper windows.

Anyone have any ideas? I attached the prefs file I'm using. This has
never happened before. Has anything changed in those files?

Using 5.1.3.10 2011-09-26 on windows xp.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Copy of racket-prefs.rktd.2011-09-28
Type: application/octet-stream
Size: 24135 bytes
Desc: not available
URL: <http://lists.racket-lang.org/dev/archive/attachments/20110928/ea78b4f2/attachment.obj>