I remember back in the earliest days of Jedi Outcast I thought I heard rumors of a program or plugin that could literally export jedi knight levels into a format that could be read by Jedi Outcast. It was supposedly very buggy, but worked.

Does anyone have any info on that? I'm very curious...

Yes, the JKLImport plugin for JK2Radiant & GtkRadiant is available here . An attempt at a tutorial is also available here .
Technically it´s not buggy (it does what it is designed to do), it just does a pretty poor job, the aproach it uses is very primitive.
But hey, try it out. Maybe you get lucky ;).