Well this is not possible by protocol. When changing status, it does not send the information directly to the contact, it goes to the messenger server then to your contact. But in the case of changing status, it sends it to all your online contacts. This is what the packet looks like:
code:
>>> CHG 13 NLN 0\r\n
<<< CHG 13 NLN 0\r\n
>>> = what is sent to the server
<<< = what is recieved by the server
13 = the transaction id
CHG = Status Change Identifyer
NLN = Online Status Identifyer
As you can see it is a global message, it does not define any contact specifically so again i say it would be impossible.
And can understand what you mean by sending information directly to plus, just as if custom sounds, and that would change the status by faking a packet, such as:
code:
<<< NLN BSY you@passport.com This Is My FriendlyName 268435492\r\n
In theory, i guess it could work, the proxy method plus uses i guess could do it
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