Unable to add new topic in IE9 (Mingle Forum w/Guest Plugin)

[Mitchell_T]

Hi – unable to create a post when using the IE9 browser on Windows/Vista. Other browsers unaffected, but most site users are on IE (unfortunately).

Full details on cartpauj forum:
http://cartpauj.icomnow.com/forum/mingle-forum-plugin-group1/support-forum6/unable-to-add-new-topic-ie9-mingle-forum-wguest-plugin-thread4184

Thanks for any help!

http://wordpress.org/plugins/mingle-forum/