asterisk users - Jan 2004 - Queue timeout problem

Hi,

I have a problem with queues and SIP phones. Timeout doesn't work!
I tried putting timeout in queues.conf and/or on the exten command in
extensions.conf but I can't get it work...
What's the problem?

Here is my extension in extensions.conf:

exten => s,7,Queue(hdqueue|t|||40)
exten => s,8,Playback(not-available)


Thank you
Edoardo