[Zope] Searching catalog via substring

Hi, I have got a ZCatalog, named "catalog" and 2 automatically-mady-by-zope-DTML-methods "search" and "report". The "search"-form submits the variable "title" to "report" which <dtml-in>s over the catalog. For example: http://server.domain.com/report?title=something So far, so good. When the title contains "something" as a word, the object is found. What I would like to do is automatically searching with "*" concatenated to the beginning and to the end of the searchstring, so the object "something" is found when the user enters only "some" or "thing". Can anyone point me to the right direction? Many thanks in advance. Lars Reineke