vm issues with virtualmin

I ahve one install with vmware as the host and another as openvz as the hypervisor. Neither of them are operating correctly. One the vmware one imap refuses to authenticate at all. smtp works fine.

on the openvz installs are having all kinds of issues. from postfix not getting hostname(centos 5 and ubuntu 14.04 lts) to smtp refusing to authenticate via sasl because it can't see pam(cent6). are folks having issues with virtualmin under various hypervisors?