[Zope] mailhost location problem

Hi, since restructuring my zope objects to tidy up the project's root folder, I've been able to get objects working, but others not. I have put things like some zsql and python methods in a folder called 'helpers', so I can call a python method which spits out a dropdown HTML element, from any page as <dtml-var "helpers.category_dropdown()"> but I can't seem to make a <dtml-sendmail ..> tag work, however I refer to the mailhost object living in helpers. I've tried <dtml-sendmail mailhost="helpers/MailHost">, helpers.MailHost, and everything else I can think of, but it complains it still can't find it. Could anyone tell me how to refer to this mailhost object? TIA Ben Avery YouthNet UK (p.s. Zope 2.5.1, Python 2.1.3, Solaris 7)