boost hangs when building

[misty.de.meo@…]

I can't get the most recent version of boost to build in MacPorts. When attempting to install it, it hangs at the following point while compiling:

darwin.compile.c++ bin.v2/libs/regex/build/darwin-4.2.1/release/address-model-64/architecture-x86/threading-multi/wide_posix_api.o

    "/usr/bin/g++-4.2"  -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -pedantic -dynamic -no-cpp-precomp -gdwarf-2 -fPIC -arch x86_64  -DBOOST_ALL_NO_LIB=1 -DBOOST_HAS_ICU=1 -DBOOST_REGEX_DYN_LINK=1 -DNDEBUG  -I"." -I"/opt/local/include" -c -o "bin.v2/libs/regex/build/darwin-4.2.1/release/address-model-64/architecture-x86/threading-multi/wide_posix_api.o" "libs/regex/build/../src/wide_posix_api.cpp"

By "hang", I mean that I've left it at that build stage for hours with no progress.

I do have the previous version of boost installed in MacPorts; the problem is when upgrading. I'm using Mac OS X 10.6.7 with GCC 4.2.1 building for 64-bit.