Connecting my Handheld to NT to get mail

I am trying to use a Phillips Nino (Windows CE)to connect to my NT box and get mail off the server. When I connect to an outside provider, the modems work fine but when I try to dial my NT box, the 2 modems can't negotiate correctly - I get a high pitched sound during the handshake - that's when I know they won't connect up.

My laptop and home computer can hook up fine with the NT Box and get mail but my handheld will not handshake with my NT.

My question is: Are there different ways to make the modem respond to outside calls. Is there something I can change with my present modem setup to make the handshake go through when my handheld is calling??? And is this a rediculous question!?!?