Ok, here's the dig in regards to the 7965: I'm going to recommend 9.4(2)SR2 (or later). Don't get me wrong, firmware version 8.5(4) is a beautiful and stable firmware for the 7900 series phones but with 8.5(4):
1. You need more files (like XMLDefault.cnf.xml);
2. You're going to rip your hair out with the configuration;
3. If you stick with 9.X firmware, you can use the 7965 "base" template configuration file onto the 6921.
Ok, so what do you need?
First, you need the firmware on the phones. Like I've mentioned above, I'd recommend using 9.4(2)SR2 and later.
Next, a file called dialplan.xml. A good sample can be found below:
<DIALTEMPLATE>
<TEMPLATE MATCH="*" Timeout="5"/>
<TEMPLATE MATCH="1300......" Timeout="0"/>
<TEMPLATE MATCH="*#" TIMEOUT="0" REWRITE="%1"/>
</DIALTEMPLATE>
Explanation:
<TEMPLATE MATCH="*" Timeout="5"/>
Enter any numbers and after the last digit, wait for 5 seconds before dialing.
<TEMPLATE MATCH="*#" TIMEOUT="0" REWRITE="%1"/>
This means dial any number, however, when the "#" is entered, do not wait for the timeout and dial immediately.
<TEMPLATE MATCH="1300......" Timeout="0"/>
This means match the first four digits of "1300" and expect the next 6 digits. Timeout is "0" means after the 6th digit, dial immediately.
Finally, you need the SEPmacaddress.cnf.xml file. Fortunately, I've already done the "heavy lifting" for you. For a sample template, go HERE. There are two sample files there: One for an 8961 and another for a 9971. Choose which of the two you want to use. There are also some settings mandatory there.
As what Sreekanth has noted, don't forget DHCP Option 150. This is very important.
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