Problem with SMPTE vs Frames

Hi,

I've got a batch script that iterates through a number of files and, among other
things, needs to set the timeline range.  Some of these files have timelines set
to frames and others have them set to timecode (i.e. SMPTE ).  I'm setting the
range using:

myPlayerControl = FBPlayerControl()

myIN	= FBTime(0,0,0,0)
myOUT 	= FBTime(0,0,0,0)
	
myIN.SetTimeString( IN ) # where IN = '00:00:03.10' (23.976fps)
myOUT.SetTimeString( OUT ) # where OUT = '00:00:05.04' (23.976fps)
	
myTimeSpan = FBTimeSpan( myIN, myOUT )
FBSystem().CurrentTake.LocalTimeSpan = myTimeSpan

This works fine as long as the timeline in the file is set to timecode; but it
fails if the timeline in the file is set to frames.  I cannot find a way to
force the timeline to timecode, or even figure out whether it is set to timecode
or frames.  

Anyone have any ideas?  

Thanks!