Came across a customer scenario where they wanted to have their 2nd line on the phone setup as CFwdall to some external number. Customer complained that when he is trying to do that for 2nd extension line, the Softkey for CFwdall is getting greyed-out.
This is not possible in Call manager System.
You can only do Call forward all on Primary line, not on any other line.
Go to ccmuser GUI for that user and do the call forward all for the other line from there.