Informix full text searching

I use Informix 4gl/SQL/Online 4.1 a good deal for numeric applications. Unfortunately, I've had some problems with large text fields. What I would like to implement in many cases is a "full text" search; the ability for the user to search for records by matching individual words or word groups in a large text field. Of course, anyone can search a large text field by searching where field matches "*word*", but this is very slow and Informix does not use any indexes on the field when you search using a leading wildcard. I've thought of implementing this kind of search by creating a detail table with each record consisting of a single word or word group from the main table. This detail table could then be indexed and searched fairly quickly. The problems with this scheme, aside from the extra disk space needed to hold the detail table, involve finding a good method of breaking down normal text into words and word groups while avoiding "noise words" like "the", "and", and "a" that no one would want to search on. Has anyone out there implemented such a scheme using Informix?