Zimbra and SSO

[maxxer]

Hi

I'd like to know if anyone ever developed an open source based SSO solution which includes Zimbra.
I'd like to share Zimbra's ldap authentication with other webapps I run in my intranet, which means when I login in Z I should then be logged in into the other apps as well.
And if I should be allowed to login into one of these webapp, using zimbra's ldap, but found then be automatically logged in into zimbra as well.

thanks