[SWLUG] modem fax question

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i am running mandrake snf7.2 firewall on a seperate box which also does masq 
duty for a few other boxen
i also have a modem in the box which i am going to try to set up as an 
alternative net connection for when (as occasionally happens) the cable goes 
down (though ntl seem to be better than they were when i first got cabled)

q. assuming this works, -old modem- how easy/difficult would it be to also 
use the modem to send an occasional fax from a workstation on the local 
network?
i sent a fax once before i had a firewall or cable using some gui prog i 
can't remember now, am i looking at installing a prog on the firewall and 
doing X forwarding or whatever it's called? or can i use fax software on my 
workstation but somehow get it to dial out using the modem in the firewall 
box? i'm sure that linux makes this a possibilty i'm just wondering if it's 
going to be complicated for a newbie like me,
it just cost me £3.50 to fax two sheets to the u.s., it would be nice to 
avoid this in future:-)

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