I tried &F2 with the Hayes accura 144 and Hayes accura 144-HH setup... nope.
but you did get me on the right track....
For my Packard Bell 204CD using a Hayes Accura 144 fax modem I used the following to get upto 1700cps successfull transfer rates with no re-transmits...
in the edit connection setups... I created a new one call KensIBM
in it I turned on only:
Hardware Handshake 19600
that's all..
Then I typed in AT&F for thewake up....
and AT S0=0 N1 &K4 &D0 W0 &Q6 X4 S37=11 for modem initialization...