* When compiling a shared lib, always include -version-info x:y (even if
   x, y are 0). PLIST gets .a, .la and libfoo.so.x.y entries.

 * ONLY when compiling a shared object (that's later opened with dlopen(3),
   NOT a shared lib), use -module -avoid-version. PLIST only gets the
   foo.so entry.

See also section #6.2 (Shared libraries - libtool) of Packages.txt (rev.
1.126 or above). I hope this makes things a bit clearer.


 - Hubert

-- 
Hubert Feyrer <hubert@feyrer.de>