I installed ZCB and can see GAL in BlackBerry Manager. I added a Zimbra user into BES and set an activation password for it. I did "Options -> Advanced Options -> Enterprise Activation" on my handheld, typed in email account and activation password. Then I did activate. The handheld shows "Activating ..." I noticed an activation email arrived in my inbox. But it has been quite a while. nothing happened so far.