Mobile Home Sync Login Window Issue 10.7.5

I have been trying to fix an issue within my environment that has been randomly occurring on various machines with various users at my site. Let me explain my environment. We are a K12 education institution that has roughly 300 Mac clients, 950 students and 120 staff members. The whole environment is setup as a Mobile Home Sync environment. We upgraded our OS from 10.6 to 10.7 over the summer. In August, multiple users were having keychain authentication issues after login and the "NetAuthAgent" wants to use the login home sync. I found that running a mass keychain reset via ServerCleanup was a temporary band-aid to the issue, but now it has come back. Random users will login to a client machine, the home sync process will start and successfully finish but then when it looks like the user will be taken to their desktop, a bright gray screen shows up and then they are quickly kicked back to the login window. The user can try to go to another machine, but the same process will happen again. I have found that resetting the keychain will fix this but it is only a temporary fix. Is there any way to do a mass fix of this issue via ARD or through the server?

Server

Mid 2010 Mac Pro

2x 2.4Ghz Quad Core

20GB Ram

2TB Hardware Based RAID with 0+1 (Homes and Shares)

160GB OS Drive

OSX Server 10.7.5

Complete Mobile Home Enviroment

Clients

Mid 2007 iMacs with OSX 10.7.5

Mid 2010 iMacs with OSX 10.7.5