I am trying to follow the wiki's instructions for creating a "Hello world" zimlet at HelloWorldZimlet - Zimbra :: Wiki, and have (I believe) successfully followed the instructions and goten expected output, up to running "/opt/zimbra/bin/zmzimletctl listZimlets" and getting com_zimbra_hello to show up in all three of "Installed Zimlet files on this host:", "Installed Zimlets in LDAP:", and "Available Zimlets in COS:".
However, I am having trouble seeing the Zimlet in the UI. I haven't done anything from my user account other than what I mention below to refresh the Zimlet list, but I tried and I can't see anything that looks like a hello anything Zimlet available. I tried a browser shift-reload, logging out and in again, attempting an /etc/init.d/zimbra restart (which seemed to hang indefinitely), and after that hung, rebooted the machine--Zimbra seemed to come up fine, but no new Zimlet.
Is there anything besides the steps in the Wiki page linked above, that I can or should do to cause the "Hello, world!" Zimlet to show up?