We have an OMERO server beta 4.03 and can connect without any problems using the beta 4.03 clients from our windows machines and a linux workstation (Centos 5.3 64bit, OpenJDK Runtime Environment (build 1.6.0-b09))
I have installed the OMEROclients on another Linux workstation (Centos -4 x86_64, Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_11-b03)) and they take 200 seconds to load up completely. The top half of the splash screen appears with the message: starting Cahing Service, but the bottom half, which contains the login boxes, takes 200 seconds to appear. Once there I can logon.
Here is the startup script in OMEROinsight_unix.sh:
cd /usr/local/OMERO.clients-Beta4.0.3.linux
java -Xms128000000 -Xmx256000000 -jar omero.insight.jar
As a poosibly relevant aside, when stating ImageJ it open almost immediately, but the bouncy icon contiinues for some time (possibly 200 seconds!)
I've opened up the firewall ports 4063/tcp, 4063 udp and disabled SElinux.
Bernie