I´m trying to conect a Philips PBX with elastix trough IP extensions of the Philips. The Philips extensions are acting like trunks in Elastix. Well, now i can made outside calls with elastix, trough Philips PBX, but when I call from any extension in Philips to the extension connected to Elastix i heard a busy tone.
My scenario is similar to yours.
Sorry for my poor English.
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