484 Address Incomplete

Hi,

I have 2 asterisk servers, 1 in each of 2 locations.
Location2 has a queue with 2 local extensions permenantly assigned to it.
From Location1 I wish to log into this queue.

Before the queue I had this dial plan in location1
*8XX
8XX

so users could pick up voice mail and dial extensions in location2.
A similar dial plan exists in location2, so location1 can be dialed (context is set to from-internal at both ends of the trunks)

To enable logging onto the queue I need to send 8XX* and 8XX**, but I don’t seem to be able to get the dial plan correct.
I’ve tried
8XX*
8XX**
and
8XX.
but I get “484 Address Incomplete” everytime.

Am I doing something wrong, if so, what?
Can this not be done?

Thanks