Network communications fails with R13B02-1 on OS X

[Dave Bryson]

Yesterday I upgraded to otp_13B02-1 from R12-5 on OS X 10.5.8. I  
notice today that any form of network communication between nodes  
seems to fail. Trying to start slaves on the same host (which I was  
able to do before the upgrade) fails with an {error,timeout}.  Even  
doing a simple 'net:ping(node1@REDACTED)' on the same host between two  
nodes fails with a pang.   I can run the same exact tests on Ubuntu  
with R13B02-1 and they pass with flying colors.  Has anyone else  
noticed this problem on OS X?  Any ideas what the problem may be?

Thanks!
Dave