[BirdOPrey5]

Thank you for those suggestions... I don't know that the bburl override is needed. The problem is if I do that then someone adding an image (or really, when the cron job runs) will have the alternate bburl encoded in the post- but this is still a problem because it's a hard coded domain, it won't vary based on who's viewing it but on who was viewing it when the task ran.

I seem to have solved the "problem" by making a new bb code also called img, this seems to override the built in [img] bb code and allows me to use relative urls... so by putting "/foums" in your replacment url settings all images are correctly being given a relative url such as "/forums/images/imported/2011/..." and working well.