also, the above issue only i am facing when i try to make outbound call but for inbound call i.e call which is coming from outside to PBX via adtran is not having any issue.
Do you have to register or authenticate to Telus on your SIP trunk?
Can you enter the following debug and then try placing an outbound call
Debug sip stack messages
Debug voice verbose
Debug sip cldu
Put the debug in a text file and attach it like you did your config.