You cannot just create a new softkey, you can only work with the ones that are available in each call state.
A speed dial you can create, but it's simply a speed dial, you would need to pick up the call, then transfer, speed dial, then transfer.
iDivert sends calls to voicemail once you press it, if you don't use voicemail, you could create a fake pilot and send them somewhere else.
If you use H.323 or SIP you can create dial-peers to block or re-direct those calls.
HTH
java
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