flexfax: Problems with many modems

["Michael Wind" <Wi@Suprafilt.de>]

Hello all, 

I have a problem with hylafax an several modems.
The installation works fine and everything goes but the faxes are 
destroyed. There are many drop outs on both sides, the send fax 
and the receive fax. 
Why?
It looks like problems with the connection from faxmodem to 
computer. Has anyone hints? Like setserial or something else. 
Should i use xonxoff or rtscts.
The system ist Linux 2.2.7 on a 486-2x66 with 32 MB and 16550A.
The modems are supra v32bis and Dr. Neuhaus 28800. These 
modem run fine under Windows or Novell via Tobit Faxware.
What can I do?

Thanks in advance.

M. Wind