Problems building openmpi, 10.6.8, xcode 4

[Tim Harder]

Hey,

I am trying to install openmpi via Macport 2.0 but am running into 
trouble while building.

* from the main.log .. snip
:info:build make[9]: Entering directory `/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_tarballs_ports_science_openmpi/openmpi/work/build/ompi/contrib/vt/vt/extlib/otf/tools/otfprofile'
:info:build   CXX    otfprofile-otfprofile.o
:info:build   CXX    otfprofile-CSVParse.o
:info:build   CXX    otfprofile-DataStructure.o
:info:build   CXX    otfprofile-Handler.o
:info:build   CXX    otfprofile-Prodtex.o
:info:build   CXX    otfprofile-Summary.o
:info:build   CXXLD  otfprofile
:info:build Undefined symbols for architecture x86_64:
:info:build   "___builtin_expect", referenced from:
:info:build       _main.omp_fn.0 in otfprofile-otfprofile.o
:info:build ld: symbol(s) not found for architecture x86_64
:info:build collect2: ld returned 1 exit status
:info:build make[9]: *** [otfprofile] Error 1
* .. snap ..


I am using a 2011 MBP with SnowLeopard (10.6.8) and the latest XCode for 
Snow Leopard (4.0 I believe).

Any hint or tip to resolve this problem is greatly appreciated.

Thanks
Tim