[Zope] Invalid Header (0) error

[Rik Hoekstra]

>Does anyone know what an Error Type: Value Error, Error Value:Invalid
>Header (0) error represents ?
>
>It's interesting in the way it shows itself up. I added a <dtml-var
>a_dtml_method> to a dtml method and it generates this error. This <dtml-var
>a_dtml_method> is nested inside a <dtml-if> and would definitely not be
>rendered the first time the 'calling' dtml-method is rendered.
>
>I took out the <dtml-var a_dtml_method> and I still got the same error.
>
>I put a <dtml-var REQUEST> as the first line of the 'calling' method and
>everything then renders correctly with no error. Even the <dtml-var
>a_dtml_method> renders correctly when it should do so.
>
>Any ideas, suggestions ?
>
>
Hm, I had this a few times, but in occasions entirely unrelated to the one
you  describe. The solution always was to add a header to the DTML Method.
This was even with a DTML Method that wasn't showing. I always wondered why
this would give an error.

hth

Rik