Mongrel crashing when using gd2 with an uploaded file

using GD2 graphic library, this code
@image = Image.load(@params[:image].read)
works one time, and crashes the server the second time. usually the
mongrel window shows this error message:
[BUG] Segmentation fault
ruby 1.8.6 (2007-03-13) [i386-mswin32]
other times this error message shows up:
: [BUG] Segmentation fault
ruby 1.8.6 (2007-03-13) [i386-mswin32]
and other times, nothing.

what i see happen is that rails (or whoever) create a temporary CGI file
in the windows TEMP folder, and fail to delete it after the script
finished its job… the next time that rails get a file using POST it

I’m using instant rails on windows vista.

any suggestions on how to fix this annoyance?

thanks in advance and sorry for my beat up English…