Novell GroupWise 8 Support Pack 3 Hot Patch 1
Novell GroupWise 2012 Support Pack 2
SUSE Linux Enterprise Server 11 Service Pack 2 (SLES 11 SP2)
It was discovered after much troubleshooting and taking and reading network packet traces, that IPv6 being enabled was the cause of the issue. Once this was disabled and this issue was monitored for over 2 weeks , the issue never returned.
To check if you have IPv6 running on the server , you can also go to a Linux terminal and issue the command "ifconfig", if you see "inet6" anywhere then that is a good sign you have it running.
Also if you run this command at a Linux terminal "lsmod | grep | -i "ipv6" and if you see something like this as a result, then you do not have IPv6 enabled : "ipv6_lib 345070 0"
One way to disable IPv6 on SLES11, go to Computer | Yast | Network Devices | Network Settings | Global Options tab | IPv6 Protocol Settings, uncheck "Enable IPv6", Click OK and exit YAST. At your first opportunity Restart the SLES11 server.