[Zope] trapping login errors/exceptions

[Henny van der Linde]

Hi,

This should be very simple but I can't get it to work.

I have a method called do_login. This method can't be viewed by anonymous
users.
When I call this method just with <dtml-call do_login> a standard login
screen is presented as expected.
Now I want tot trap login errors with a try construction such as this:

<dtml-try>

<dtml-call do_login>

<dtml-except>

 <p>Login error, please try again (etc.) </p>

<dtml-else>

<p>Login ok</p>

</dtml-try>

In this construction the call to do_login always raises the exception
Unauthorized instead of presenting the standard login screen.

How do I trap login errors in an elegant way?

Is there an elegant way to trap login errors resulting from an URL? URL link
to a secured object, standard login screen presented, wrong input etc.

Thanks


Henny van der Linde