RCS on Windows - PowerPoint file

Hi,

I just installed RCS for Windows.  I used to use it on Unix all the time,
this is my first time on Windows.  I created an RCS folder and then did a
checkin of a PowerPoint file to do the initial checkin (I tried with the -i,
and with the -u as well).  When I then did a co -l, (or even just a co), my
PowerPoint file (about 170K) was overwritten with a 6 byte file and I lost
my original file.  I tried a couple other ways and the same thing happened.
It seems to work ok for some text files that I have.

Am I doing something wrong?  It's supposed to work on PowerPoint files,
correct?

Thanks!!
Sue