macports 2.0.4 breaks the usage of clang on Xcode 4.3.2

[Jack Howarth]

   It appears that the new MacPorts 2.0.4 release when clean installed from
the Lion dmg breaks the usage of clang as the default compiler for package building
under Xcode 4.3.2. If you execute 'sudo port -d install pymol', you will observe
that /usr/bin/llvm-gcc-4.2 is used when building all the required packages during
the pymol installation. I don't see this issue with an installation of MacPorts 2.0.3
which was upgraded to 2.0.4. Any idea how this got so badly broken?
             Jack