I'm having some very odd issues with US toll free numbers, when routing calls through 3CX's Skype Gateway as opposed to dialing them directly from the Skype client. This behavior is also reproduced in another Skype gateway product, siptosis. Sometimes, US toll free numbers never connect. Other times, they take very, very, very long to connect. And, in one particular case, dialing a specific toll free number for American Express from our landline, or the skype client results in reaching one automated attendant at American Express -- while dialing the very same number from our softphones, through our 3CX PBX, out through 3CX's skype gateway gives us a completely different automated attendant at American Express! Is there something in the PBX that's adding a "via" header to the skype call, or fooling with some other headers? In other words, what is different about a Skype client call, as opposed to a Skype API call, that would identify the caller differently to the callee? At a loss... any ideas?