I wanted to point out that is should deal with several issues that include a patch to solve this Host crash because of ESX Active Directory Integration.
Here is the info from the KB 1027021
When an user who is a member of more than 32 groups attempts to log into an ESXi host by using KVM, any one of the following issues might occur:
ESX/i host restarts
ESX/i host becomes unresponsive
Note: With this patch, a user who is a member of more than 128 groups can access the console, but loses any group information beyond the 128th group.
If passwords of more than eight characters are set for ESXi 4.1 system users, the set password is truncated to eight characters, and the system evaluates only the first 8 characters of the password submitted for authentication.
Note: To implement this fix, reset the password of the existing ESXi 4.1 system users after applying the patch.
As always - Test before deployment