This extension for RT 3.2 and 3.4 allows sites to "Brand" individual queues
with distinct tokens in the Subject: headers of outgoing email messages.

To enable this extension:

# cd into the unpacked distribution directory

 perl Makefile.PL
 make
 make install

# edit your RT_SiteConfig.pm library to add the following line
# immediately before the last line of the file:

 use RT::Extension::BrandedQueues;

# The only thing after that use ..." line should be the line:

 1;

You'll also need to modify any of your local email templates which use
the $rtname variable. To edit your templates, log into RT as your 
administrative user, then click:

Configuration -> Global -> Templates -> <Some template name>

For example, RT's default "Autoreply" includes this line:

 "There is no need to reply to this message right now.  Your ticket has been
 assigned an ID of [{$rtname} #{$Ticket->id()}]."


Change this line to read:

 "There is no need to reply to this message right now.  Your ticket has been
 assigned an ID of [{$Ticket->QueueObj->Tag} #{$Ticket->id()}]."