You need to add -lc++
to the link line like this:
clang -std=c++11 -stdlib=libc++ -lc++ -m64 -o ARCH.darwin_1310_i86/release/myExec ARCH.darwin_1310_i86/release/myExec.o ../../src/netcomm/ARCH.darwin_1310_i86/release/libmyExec.a ../../src/common/ARCH.darwin_1310_i86/release/libcommon.a -L../zlib -lz -L../Botan -lbotan-1.10 -lboost_thread-mt
After adding that, the missing symbols go away.