We just recently finished the upgrade from 4.5.6 to 5.0.11
When we are logged into the admin console and are working in the COS, in the Zimlet section, after I make a change to one of the Zimlets, the "Save" Tab stays Grayed out, I'm unable to save my changes.
If however, I click on “Select All” at the bottom of the screen, the "Save" Tab is now highlighted, and I can uncheck the Zimlets I don’t want that COS to have. It looks correct in the admin console. I double checked and found that this issue also happens while working in the Zimlet section on the individual account as well, not just while working in COS.
Additionally, when I log in as a user in that COS it still shows me Zimlets that COS is NOT suppose to have, even though the COS looks correct. On the user’s computer, I have cleared the Cache on the browsers, close all instances of the browser and logged back in. I have also double checked the individual's account to make sure that they are only using the COS Zimlets. I have had to disable some Zimlets to keep them from showing up, but I can’t do that with some of my Zimlets, as they are needed in another COS.
Any ideas would be gratefully appreciated.

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IBM X3650 Dual Quad Core L5310 | 18GB PC2-5300 CL5 ECC DDR2 - CentOS_PAE (2.6.18-53.1.4.el5PAE)
1 x 73GB SAS 15K 2.5" SFF HS (5543) Primary OS Drive
0+1 RAID 4 x 146GB 10K 2.5" Hot-Swap SAS HDD opt/zimbra
Release 5.0.11_GA_2695.RHEL5_20081117020711 CentOS5 NETWORK edition | CentOS 5.1 |