Cannot receive faxes in Windows 98SE

I have installed Mighty Fax on a new pc with Windows 98SE. I use af Lasat Safire modem to send faxes from Mighty Fax. That part works very well. The problem is I can’t receive any faxes. When a call comes in, the modem answers the call (DTR,RXD,TXD,OH lights up on modem) and then it disconnect. I can hear on my normal fax machine that it doesn’t connect properly – it just keep calling the modem. I’ve tried everything – other modems, other PC’s, other fax-software including AWFAX from MS, other phone lines and it’s just the same. I tried different low/high settings on the baud rate. Nothing helped.
Are there any problems / limitations in Win98SE – please help!!!

MKR Multimedia A/S – Morten, morten@mkr.dk