P4_GLOBMEMSIZE problem

[Jean-Christophe Ducom]

When I try to run a charmm job (w/ modified sizes files) on 1Gb SMP 
nodes, I get the following error message:

p8_12489: (6.243597) xx_shmalloc: returning NULL; requested 3801600 bytes
p8_12489: (6.243731) p4_shmalloc returning NULL; request = 3801600 bytes
You can increase the amount of memory by setting the environment variable
P4_GLOBMEMSIZE (in bytes); the current size is 4194304
p8_12489:  p4_error: alloc_p4_msg failed: 0
Broken pipe

What I am missing? The current size is higher than the requested size....
Thanks

        JC