i found this ZWC 5.0 Themes which helped to change the logo for single domain .
I tried to google but failed to find a way for changing the logo for multiple domains in single server.
Can you suggest me any article which explains about changing logo for multiple domains on single server.
[zimbra@mail ~]$ zmcontrol -v
Release 6.0.6_GA_2330.RHEL5_64_20100505193959 RHEL5_64 NETWORK edition.