Do you get the same error results on a non-Itanium system? What about a non-Rocks cluster?
I expect that you'd see the same results if you tried using MPICH2 since the Intel MPI versions are based on this and you've seen the problems with MPICH 1.2.7.
You should report this error through the Intel Premier Support (http://premier.intel.com) technical support site for Intel MPI. Also, since it looks like the problem might be based in the MPICH used, you could look into the MPICH web sites to see if a workaround for this problem has been posted or is known.
As for things you might try, can you put the parameter lists into COMMON areas that each subroutine will have access to? This would alleviate the problem of sending so many parameters to each affected routine. Of course, this will require some code overhaul to make the transfer.