As you perhaps noticed I am playing with the box a bit and on this 7050 there is a certain callthrough function.
Einstellungen -> Telefonie -> Rufumleitung -> Duchwahl (Callthrough)
In short: you assign the service to a called "Rufnummer", assign a code, the "Rufnummer" to be used after and you're done!
Call the number from f.e. you're Mobile phone, enter the code, dial a "0" -then you'll hear a continuous dialtone- followed by the international format number i.e. 0031xxxxxxxxxx.
This way I can call from my mobile phone (with unlimited calls in LUX) to my faxline, then over the internet with Voipbusterpro for 3,9ct per call to f.e. Holland!
Not bad...
