MPI doesn't work (Fatal error in MPI_Init)

Hi,

I have the following problem:

I have two nodes and config file:

-n 1 -host node0 myapp
-n 1 -host node1 myapp

In this way it works fine. However If I change the order of lines in config to:

-n 1 -host node1 myapp
-n 1 -host node0 myapp

It fails with the error:

Fatal error in MPI_Init: Other MPI error, error stack:
MPIR_Init_thread(658)................:
MPID_Init(195).......................: channel initialization failed
MPIDI_CH3_Init(104)..................:
MPID_nem_tcp_post_init(344)..........:
MPID_nem_newtcp_module_connpoll(3102):
gen_cnting_fail_handler(1816)........: connect failed - The semaphore timeout period has expired.
 (errno 121)

job aborted:
rank: node: exit code[: error message]
0: node1: 1: process 0 exited without calling finalize
1: node0: 123

What can be the reason for? Any ideas?