I received a call and my state changed from "available" to "on the phone" which was perfect.
Then I transferred the call to another collegue and his state changed from "available" to "on the phone".
But my state never chanegd back to "available" once the call was transferred. I had to manually set it to "available".
We're using Polycom phones and I transferred the call from the transfer button on the phone (not the usual '#' on Asterisk).
Let me know if you have a fix for this.