You said:
 RB> How can I accomplish this except in modeming mode. Please take all 
 RB> info provided into consideration.  Thank you very much! 
There is only one way to disable call waiting when you're the CALLED PARTY 
(i.e. NOT dialing out), and that's by using three-way calling as I described 
previously.
After you have picked up the incoming call, flash the switchhook, wait for 
three beeps and a dialtone, dial *70, you'll get three beeps and a dialtone 
again, flash the switchhook again.  Dialing ATA*70 isn't a valid AT command, 
and dialing *70 on receipt of a call doesn't work.  To my knowlege, none of 
the HAYES modems (This IS the Hayes echo, BTW) have a "flash" function - 
you'll have to code it yourself.  I can't speak about a USR.
The answer string Dennis gave you should work, but the "!" is the key - 
that's a switchhook flash on some modems, but not all (most do not).  It also 
requires three-way calling to work.  
You might try ATX0H1,H0,DT*70;|~~~ATH0,X4A| which should also give you the 
correct sequence more or less.  Again, hinges on three-way calling to work.  
Try it and see - some RBOC's have three-way set up so you can use it a la 
carte with a nominal fee per use instead of adding as a feature.  (BellSouth 
does.)
It's a tough row to hoe.  You're far better off getting rid of call waiting.
-dw
--- 
---------------