Password Change Error on OWA

I have setup Outlook Web Access 5.5 on Win2k and placed it in the DMZ.The LMhost file has the required entries as well as all required ports have been opened on the firewall.When changing password via OWA the follwing error is displayed :
Internet Service Manager
for Internet Information Server 5.0

Configuration information could not be read from the domain controller, either because the machine is unavailable, or access has been denied.
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I also attempted to change my password from the owa server by logging in and it could not could my contact my domain now.
To RECAP : It does take me all the way to change password button with the credentials but displays the error above when clicking OK.