I've been trying to upgrade from ZCS 5.x to ZCS 6.0.1 on an OpenVZ virtual machine running Ubuntu 8.04. This vm has been running ZCS 5.x successfully for quite some time. The install seems to get nearly all the way completed until I get:

Installing common zimlets...
com_zimbra_bulkprovision...failed. This may impact system functionality.
com_zimbra_phone...done.
com_zimbra_local...failed. This may impact system functionality.
com_zimbra_ymemoticons...failed. This may impact system functionality.
net_inova_gmaps...failed. This may impact system functionality.
com_zimbra_date...failed. This may impact system functionality.
com_zimbra_cert_manager...failed. This may impact system functionality.
com_zimbra_email...failed. This may impact system functionality.
com_zimbra_url...failed. This may impact system functionality.
Finished installing common zimlets.
Installing network zimlets...
com_zimbra_license...failed. This may impact system functionality.
com_zimbra_hsm...failed. This may impact system functionality.
com_zimbra_mobilesync...done.
com_zimbra_cluster...failed. This may impact system functionality.
com_zimbra_delegatedadmin...failed. This may impact system functionality.
com_zimbra_backuprestore...failed. This may impact system functionality.
com_zimbra_convertd...failed. This may impact system functionality.
When I check /var/log/messages it seems the problem is java related. I get a slew of these messages:

Could not create the Java virtual machine.
I know this is usually a memory problem so I stepped the memory up from 8192MB to 16384. Still no dice. I watched the memory usage and it didn't even get close to pushing that.

Any tips, or suggestions would be greatly appreciated.