I have reversed the configure option when building gretl from CVS:
if you want openmp support, please use
--enable-openmp
In addition I'm omitting openmp support from the snapshot builds
for Windows and OS X.
This is surely something we'll want to come back to, but for now,
in most practical-use cases, openmp slows things down a little
while adding bulk to the pre-compiled packages.
Allin