Thanks a bunch! I'll try it now.
Oh... now I remember, I have PATH'd the OpenAL32.dll that came with SFML 1.3 and then built the SFML from svn.
Maybe the OpenAL guys change some constants in each build... that's crap man, they shouldn't, like OpenGL.
Sorry for the troubles.
EDIT: I did as Nexus said and it worked.
I think that some app/game installed OpenAL on windows/system32.
That directory has more precedence in the enviroment variable PATH than the one I use to dump all sdk's dlls.
I think that if the OpenAL32.dll is in the same directory as the application, then this won't bother at all.
Problem solved.
Thanks again!
-Martín