[Zope] How do I use the math module ?

Hi, I have a simple question - how do I use the fmod function in the math module with dtml ? I've tried something like this(and a lot of variants): <dtml-if expr="_.math.fmod(x,y) == 0"> do something </dtml-if> What is it for: I have some words returned from a search which I want to be displayed like this: word_a word_b word_c word_d word_e word_f word_g word_h word_i Thanks in advance. Regards ------------------------------------------------- Anders Holmbech Nielsen | Tlf: (+45) 70 22 56 00 Software Engineer | Fax: (+45) 70 22 57 00 Integrator Uniware A/S | http:/www.integrator.dk