eac3to of cause.
http://forum.doom9.org/showthread.php?t=125966
it is a command line program i personally have no problem with that.
it can do what you are looking for.
Quote:
-23.976/... define source fps to be "23.976", "24.000", "25.000", ...
-changeTo24.000 change source fps to "23.976", "24.000", "25.000", ...
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