If your system was converted from a 4.0 or below database to a 4.0 or higher SDS database, someone set that extension up as a local dn, meaning that it is only used on the local system and won't/wouldn't be shared with the rest of a cluster. Unfortunately a downside to this is you can't add it or really edit it anymore. In order to change this, you'll need to either work with your VAR, or if you are a VAR, call support and have them walk you though getting access to the SDS Debug area. SDS Debug is a hidden set of forms that let you work with and correct these types of errors. You should however only do this under the supervision of support has it is direct Database access and changes in here can potentially effect other areas of your system.
