sorry but that cannot be done, the CUCM server expects the softkeyevent=5(CFwdAll) SCCCP message in order to set the CFA number.
CUCM matches the DN and TCPid from which the message comes to modify the DB CFA field.
you cannot emulate that from a POTS line
when you log into the ccmuser page the change is done directly into the DB using that GUI.
HTH
HTH
java
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