[Zope] ZSQL 'Like'

I'm new to Zope and I'm trying to put togther a ZSQL search method. I want to take the input from the user form and create a LIKE clause rather than an = clause. This means I need to tack a percent sign onto the input. If the user enters 'Jim' I need the SQL method to create, WHERE firstname LIKE 'Jim%'. Whats the best way to do this in Zope? thanks jb