Can I get xine to recognize *.mp4 as *.m4v?

Hi,
   I'm able to play *.m4v files successfully in xine. If I rename one
of these files to *.mp4 then xine tells me:

"There is no demuxer plugin available to handle 'xxx.mp4'."

Same file, just a different extension.

   Is there an easy way to get xine to recognize that my mp4 files are
really just m4v?

   If I understand the xine faq it's really m4v which isn't the
standard and xine should be able to play mp4 with no problem so I'm
wondering if I've not built something in correctly?

   I'm on Gentoo and running xine-ui-0.99.6 & xine-lib-1.1.19. If it
matters the files were created using Handbrake.

Thanks,
Mark

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