This is a known problem unrelated to GBMV, but it does depend on the CHARMM release version and how it was compiled. There was a thread on this topic a while ago, probably in the "Bug Reports and Fixes" forum.
It appears that there's a major thread in the "Installation and Performance" forum, and one fix that involves shell (bash or tcsh) setup, esp. on some x86_64 RedHat based systems.
I recall a source code fix as well, which was added to CHARMM, possibly c32b1 or later (I'm exactly not sure).
Edited by rmv (05/09/07 07:35 PM)