AddQueueMember for remote agents

I’m trying to use the AddQueueMember manager app to add remote dynamic agents (i.e. member’s cell-phone) to the Queue. The user gets added to the queue and can receive calls and participate normally. My syntax for interface when adding a user is something like:

SIP/TRUNK/XXXXXXXX (where the X’s represent a real number)

The issue i’m having is on the return code for that member’s status. It’s always 4 (Invalid) until the member takes the first call, then 0 (unkown) until they log out of the Queue (with RemoveQueueMember).

Is this normal, or how can I get the queue application to recognize remote member’s status?

I’m using asterisk-1.2.10