[amelia] Using Amelia on a Cluster

I have been able to run the "multicore" option of amelia on a single (Linux) computer with 8 cores, but I am having problems porting my program to a (Linux) cluster. Specifically, I have requested (through the PBS resource management software) a single node with 16 cores. My program appears to run correctly, but then gets killed by PBS (error message: ncpus 4.01 exceeded limit 1). In the amelia function, I'm setting m = 5, parallel = "multicore", and ncpus = 1. I've tried other values for ncpus (including 5, 10, and 16), but the job still gets killed. (Note: It does not get killed if m = 1, but that defeats the purpose of using multiple cores.) Is the amelia function trying to spawn threads of which I am unaware? J. Huband