Need a little regex help

[Commonn Systems]

Hello list!

After reading the list pretty much everyday for a month now, going 
through the docs, manuals and a lot of googling (which always brought me 
back to the list anyway), I have finally decided which way to go to 
filter access to two SSIDs, for 2 groups.
I am using FR 2.1.11 on Debian squeeze, against an AD domain with LDAP 
membership lookup. I have 5 AP registered with FR, they each have 2 
SSIDs that show in the request as MACADDRESS:SSID_ABC.
Based on Phil Mayers  on this post, 
http://freeradius.1045715.n5.nabble.com/How-do-I-have-one-Freeradius-server-hosting-multiple-ldap-instances-and-associate-each-SSID-with-pare-td2847210.html#a2850433 
,
I would like to match the last 8 characters of the Called-Station-Id, 
"SSID_ABC"

authorize {
    if (Called-Sation-Id == SOMEREGEX:SSID_ABC) {
      update request {
        Tmp-String-0 = "Staff"
      }
    }
    elsif (Called-Sation-Id == SOMEREGEX:SSID_DEF) {
      update request {
        Tmp-String-0 = "Students"
      }
    }
}

Everything is working great, this is the last piece of the puzzle to 
finalize the project.
I understand, this does not have anything to do with the wonderful 
software that freeradius is, but from what I have read, lots of people 
on this list are very skilled with regex. Thank you so much for all the 
work and help you put in here.


Tossi