Beating a dead horse (.m4v video help)

A digital copy of Hulk was included in the Blu Ray special edition DVD. This is my 1st attempt to get a video on a portable device and I'm stuck.

I downloaded the CD to my computer via Itunes (on a Mac) and it was already in the .m4v format, which shows to be a format that BB can use to play video. I copied the file and dumped it into the correct area of the BB but when I try to play it tells me, "The media being played is of an unsupported format".

If I click the file from My Computer when the BB is hooked up the video works fine. Just not on the BB itself. Any ideas why this isn't working? I'm on a Curve through T-Mobile if that makes any difference.