i got commtools to work pretty good w/ vfp 5.0a.
the vfp samples wouldn't run under 5.0 but a little modification made it work.
i had a few problems but they sent me an update that seems to have resolved it.

i was getting gpfs with the getcarrierspeed function ( don't remember exactly what it was called ) but ended up not using. that may have been fixed in the update also.