As far as I know ACML 4.3.0 is the first version to support the Open64 compiler but unfortunately the OpenMP build is missing.
I think you'll have to wait for the next release of ACML or use a different compiler suite.
We did not build an Open64_mp library for 4.3.0 because of a bug in our openmp code.
But this has been resolved. Stay tuned for a new Open64 build that includes openmp.
We will be posting this very soon!