How do I specify 64-bit machine architecture when building boost libraries with bjam on solaris?
Not a real answer, just a note - Sun compiler is something boost has always had trouble with. Only fairly recent versions are supported and you need STLport. Take a look here and here.
You might want to play with the [compiler options] part of the module syntax.
Found this specific link that tells this should work:
bjam toolset=sun stdlib=sun-stlport address-model=64 stage
No doubt, it requires Sun Studio 12.