Thanks for your reply argv0.
Reading this post make me thought that there are more people with my same problem, but the DLL I was tring to create was for XChat (another IRC client). I successfully compiled the DLL without errors, but in runtime, the MessageBox didn't work well, here it is what happened with it:
http://forum.xchat.org/viewtopic.php?t=5661Does somebody know how to solve this?