bah cant you just Register the "MessengerPlus_SetName" message and use SendMessage API to send your new nick without it being a plugin?
this is the Visual Basic source code im talking bout.
code:
Public Function SetNewName(ByVal sMessage As String) As Boolean
Dim nMsg As Long
nMsg = RegisterWindowMessage("MessengerPlus_SetName")
Dim nResult As Long
nResult = SendMessage(HWND_BROADCAST, nMsg, StrPtr(sMessage), 1)
If (nResult = 0) Then
SetNewName = False 'Can happen if the user if offline
Else
SetNewName = True 'There is no absolute way to detect if the function was successful
End If
End Function
then like use the commandline way Stigmata mentioned and use like "Addnick=- Brb Playin teh Gamez"
and call the function with a nick thats already in a preset variable?
otherwise someone has to do some IMessenger pointer finding