can't edit group masthead on Production

I've tried to edit the masthead for the Curriki Team group multiple times on Production, but clicking the Submit button does not resolve the page; I am left looking at the edit form without the page refreshing to show the edit.

http://www.curriki.org/xwiki/bin/view/Group_CurrikiTeam/?action=editmasthead#

I am simply trying to update the group description to show (instead of what's there):

Curriki employees use this group to share resources, communicate about issues of interest, and test the web site.

I made myself a group leader but was still unable to change it successfully.

I was unable to duplicate this problem on current.dev.