Gengbin Zheng, one of the leading developer of the Charm++ and I managed to get Cactus compile against the AMPI (http://charm.cs.illinois.edu/research/ampi). The patch against Revsion 5120 is attached. The major changes are in the flesh to deal with global variables. We started with PUGH to get started and changes in Carpet could be done later on. NR applications might not benefit from this work though this effort could make Cactus appealing to many other applications as a computational framework.