[Koha] Omeka / OHMS issue

We have a new installation of Omeka. When I try to upload an OHMS XML file, whether zipped or not, I get the error: LogicException OHMS file must be validated before retrieving the list of columns. Along with a stack trace. Any Omeka users run into this one? Thanks! -- Chad Roseburg Assoc. Director / IT Automation Dept. North Central Regional Library