Without restarting msn messenger in some way (or let it re-initialize), soft-patching will not work...
Skinning is mostly changing resources (in msn messenger case) and resources are loaded (again in msn messenger case) when it starts, it isn't loaded on-demand.
Skinning can't be compared to loaders and the likes because those all involve only changing some small bits and pieces of code in memory (often only a byte or two). Skinning involves changing whole area's of memory without to mention all the links and other variables and code that calls that memory...
Also, if you want to get msn messenger to reload the resources without restarting, good luck with the trials and the thick ASM book you'll need...
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