Search Service Problem

I am using DFC Search Service api to get the results from docbase. During the execution of the program I see this exception on the console.

[DM_FT_INDEX_E_NO_FULLTEXT_PLUGIN_LOADED]error: "The fulltext query plugin did not initialize with the fulltext search engine 'dsearch' specified in the server config object. Please ensure that the search engine is functioning and is configured correctly."; ERRORCODE: 100; NEXT: null

I still get the results back successfully, but want to know why this exception is coming. I don't have full text enabled on the docbase hence no full-text server and agent objects are available.

One other observation, If i run same program on a different docbase (dev environment) I don't see this exception. Keep in mind that dev docbase also not configured for full text indexing.

Please Suggest.

SG