We were in the same situation, our switch (G3r v8.4) doesn't have licensing activated for QSIG. We did get the CLID to pass through ok when calling an Avaya extension from a Cisco extension. Go to your Trunk settings, on page 1, midway down, and look for Codeset to Send Display. Set that to 6. On the Cisco side, we've setup an MGCP/PRI trunk back to the Avaya. When a call is placed from Cisco to Avaya, the CLID goes through while the phone is ringing and before the phone goes off-hook. When a call goes from Avaya to Cisco, the CLID simply shows the extension while ringing (minor inconvenience) and shows the full CLID when the Cisco phone goes off-hook.
Hope that helps,
Bill