First, before you even try to call trought the gateway using netmeeting, you will need to do a basic setup to make the Quintum gateway work.
Until you could make call using a normal H323 device, like another Quintum or a Cisco ATA device,it wil a complete waste of your time try netmeeting.
I could give you a hand puting a basic setup on the gateway to allow calls from the Net to the PST side of the gateway.
The gateway will need to be on a public I.P. address where I could access it from the outside.
It takes about 30 minutes to get it going.
Are you sure that the Quintum is the kind that have the FXO type of interface????
Those FXO ports need to be conected to the dial tones provided by the phone company or the internal PBX equipment.
Post your contact information if need help.