Newbie need help on MPICH install

[xiangdong shi]

I am testing MPICH on four machines running COREL LINUX 1.1 (2.2.14
kernel). I have set up the network such that they can do rsh without
prompting for password. When I configure MPICH on the one the machine
I plan to use as server, however, the log complains
 
checking whether /usr/bin/rsh works ... no
Errors while trying to run true on mpi0 with rsh
mpi0: Connection refused

mpi0 is the name of the machine.
I also ran test on a system running Red Hat 6.2, getting the same
error. Please help. Thanks.

Xiangdong