Migrating from sourceforge bug tracker to RT

I was under the impression that somebody had developed some tools to take the
XML generated by sourceforge bugtracker export (using URLs like
http://sourceforge.net/export/sf_tracker_export.php?group_id=19506&atid=119506)
and import it into RT. However, I’m unable to find anything that actually does
this. Am I mis-remembering some other type of migration script for RT (maybe
from or to Bugzilla?) or has anyone done anything like this?

@alex