[Zope-dev] geting relative url in a dtml tag

I've defined my own dtml tag, i.e. <dtml-foo>. I want to get the relative path of the 'calling' object for that tag, in <dtml-foo>'s __init__ method. I.E. if i have a dtml-method 'index_html': <dtml-foo bar> When I edit the 'index_html' method, <dtml-foo>'s __init__ method gets called, and I want to get something like '/zope/index_html' in the __init__ method. It's easier in the render() method since the REQUEST variable is available. It's not available in the __init__() method. Any ideas? -Brett