java.lang.NullPointerException

I have my error logs mostly empty, but I keep getting

2007.10.29 12:09:11 [org.jivesoftware.openfire.ldap.LdapGroupProvider.populateGroups(LdapGroupProvi der.java:682)

]

java.lang.NullPointerException

What exactly does this mean and is there anything I can do to correct it?

Setup:

Windows 2003

Openfire 3.3.3

LDAP with AD

MySQL DB

This has already been answered at:

Hope it helps