[Zope] cannot change property of type lines permanently

[Marcus Bergmann]

Hi,

I'm trying this:

<dtml-call "calendar.mailaddresses.remove(REQUEST.mailaddress)">

where 'calendar' is a folder, 'mailaddresses' is a property of it (type 
is lines) and 'mailaddress' is a variable the DTML method received via 
an HTML form.

After the request, the removed line entry seems to be gone. It's not 
shown in the ZMI or in my HTML site which shows me the mailaddresses. 
But if I restart Zope the removed line is there again.
Also if I copy the folder, then the copy shows me the removed entry in 
its properties.

Any suggestions?

Thank you,
Marcus