Unattendand Call Transfer - REFER in early dialog state

[BlueCall]

Dear all

In real life calls are being transferred also before the new destination has answered the call.

Even if RFC's probaly did not think about this call transfer situation in early dialog state there is an absolutely need in real live situation.

So my question is how to handle the call transfer in JsSIP when the destination has not already answered the call.

Let me explain the situation:
A calls B, B answers the call, then B holds A and B calls C. Now B wants to transfer the call to C while C has not already answered the call.

This transfer is a real live situation and we should be able to handle it when using JsSIP.

Thanks for any help and support or plaese let us know what we can do that JsSIP will also support transfer a call in early dialog state.

Best Regards, Samuel