I was told it was a jig by the person who taught me it but to me it didn't feel at all like a jig. Which was the reason i wanted to know the name of the tune so i could find out where it was from or what was different about it. Thesession says it's a slide, as do other places, and that's certainly more in fitting with what the tune feels like it should be to me.
Just my opinion, please don't shoot me for it.