So what you want us to do is come up with a way to trick the telephone provider in your country ?

Is that it ?

(Personally I totally agree with Wizbang that bits on a line are bits on a line - not a tiff - not a jpg - not anything until they get deciphered at the other end. No telephone provider is going to intercept a string of bits and then try to decipher what they may be, just so they can allow them through or reject them)

What country is this where the cost of a telephone connection costs thousands of dollars and when you have a line installed it can only be used for one purpose ?

I think somewhere here the facts are not adding up.

Could I suggest you test the theory that a Fax Line is only for faxes by plugging a phone in each end and trying to talk using the fax line (voice is not the same as fax data so by your theory should not be allowed on the line)

Also try plugging a computer into the fax line and try dialing up a dial up internet provider - I am sure one of your collegues can supply you with a dial up number just for testing, since broadband connections in your country must cost a bundle.

At some stage you may have to tell the "management" that their expectations are unrealistic - and your abilities are not the problem (you certainly are tenacious which is a worthy quality for a programmer)

I hope you are not in a country where they chop off your head for failure