Messenger Plus! provides developpers with some functions they can use in plugins. But these functions are rather limited and pointed towards stuff for Messenger Plus! itself (showing a toast, parsing commands, etc). Though, it also exposes the Messenger object to the developper which can be used for more advanced things or things pointed towards Messenger directly.
But all this can also be done without Messenger Plus! if you know how. What you require is a way to hook Messenger, subclass stuff, etc. All advanced stuff, but not impossible.
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MSN Messenger itself does provide some APIs (but a bit limited) in the form of the
API of Windows Messenger,
the Activity API (
official forum) and there is also the
Active Accessibility API which can be used for some stuff.
Other info can be found here (on MSNFanatic):
introduction to messenger api type library
introduction to msgrobject
MSN Messenger Programming
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What you need (if you want to do the same as with the other IMs) is a way to hook a conversation window and trap the triple pressing of the CTRL key. Together with this, I assume, you need the IP address of the contact (which can be a problem) so you can parse that to your WigiWigi app and handle it from there.
Both main problems, the convo hooking and the IP getting, have been shown to be somewhat problematic without using some dodgy/crappy workarounds. This said, if you do go along with a plugin for Messenger Plus!, the first problem can be solved by using commands instead of tripple pressing CTRL. And the IP getting is rather easy to solve as you obvioulsy can send your own IP to your contact (and thus to his plugin).
But as said, it requires people to have also both Messenger Plus! and the plugin installed (and on both sides; you aswell as your contact).
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Your best shot is to wait for someone who knows how to deal with all this, is an advanced programmer and has experience in this sort of stuff. In the mean while you can delve a bit deeper in the above links as many stuff can be found out with some research (I only posted some basic links out of many). Also, you could take a look at the Messenger Plus! Plugin SDK to know what it does or what its capabilities are (
here). And don't forget to search around in the plugin section of this forum