Hi
Yes it is possible and explained in skinning documentation.
You must use MPTools.exe in command line.
quote:
MPTools.exe is a program that's distributed with Messenger Plus!. It makes all sorts of calls to the main program for all kinds of reasons, it's a helper tool. Although it was also distributed in previous versions of Messenger Plus!, it was not meant to be used directly by end-users or other developers. This is not the case anymore as MPTools.exe can now decode and encode UIB files when the proper command line parameters are used.
Here is an example of how to decode a UIB file:
MPTools.exe /UIB=Decode /Src="C:\uibfile.uib" /Def="C:\deffile.txt" /Style="C:\stylefile.txt"
And here is another example of how to re-create a UIB file:
MPTools.exe /UIB=Encode /Def="C:\deffile.txt" /Style="C:\stylefile.txt" /Dest="C:\uibfile.txt"
/ 
