[Zope] Weird Problem with Script(Python)

[Andreas Pakulat]

Hi,

I've got a Script(Python) which is a method of a ZClass, now if I call
this script using an instance of the ZClass I get:

Error Type: IndexError
Error Value: string index out of range

The script is called from a form, which set's some variables in the
request. The script itself also has parameters which default to None and
then checks if they are set, so that these settings override the
request-variables. Anyway, even If I comment out the whole code I get
this weird error. Here is the PageTemplate snippet containing the form.
How can I track down this problem? I really have no Idea how to get to
the point where this Error comes from

<form method="POST" action="vergeben" 
	tal:attributes="action string:Arbeiten/${request/arbeit}/vergeben"
	tal:condition="python:Attribute.getProperty('Status') == 'zu vergeben'">
	<input type="hidden" name="DestinationUrl" value="index_html" 
		tal:attributes="value python:here.absolute_url()">
		<table	border="0">
		<tr>
			<td><span class="Arbeit">Name des Studenten:</span></td>
			<td><input size="40" type="text" 
				name="Studentname" value=""></td>
		</tr>
		<tr>
			<td><span class="Arbeit">Email des Studenten:</span>
			</td>
			<td><input size="50" type="text" name="Studentemail"
				value="">
		</tr>
		</table>
	<input	type="submit"	name="Vergeben"	value="Arbeit vergeben">
</form>

Sorry for the german text, but I don't think that it is a problem.

Andreas

-- 
Do nothing unless you must, and when you must act -- hesitate.