[Zope] illegal characters in url error

[Paul Rudin]

>>>>>  Dieter Maurer <dieter@handshake.de> writes:

  > Paul Rudin writes:
 >> I'm writing a simple file upload web page. I've got it working
 >> most of the time; however when file names have certain characters
 >> in them I get errors like this:
 >> 
 >> Zope Error Zope has encountered an error while publishing this
 >> resource.
 >> 
 >> Error Type: Bad Request Error Value: The id "[X=X].foo" contains
 >> characters illegal in URLs.

  > Zope restricts ids to contain only characters legal in URLs (and
  > space).


Ok, thanks. So why does using the result of quote_url_plus as an id
also fail? Surely such a string should necessarily consist of
url-legal characters?