This seems to be an issue with document.createElement in IE6.

The solution for me was to grab the newest copy of FEC from Numinix website and replace:

/includes/modules/pages/fec_confirmation/jscript_jscssloader.js with the one from the new kit.

I thought I was running the newest version of FEC, but apparently not.

This seems to have fixed the IE6 issue.

Compare the files above for the diffs.