[Zope] Is it possible to extend Zopes WebDAV authentication?

Hello! I'd like a little help, please :) I have a site that uses PluggableUserFolders for its acl_users. The web-based portion of the login process locks out a user after 3 unsuccessfull attempts at the password and i'd like to be able to do something similar for users who try to connect via WebDAV. I'm sure something like this should be possible but am uncertain where to begin. Is it possible to override the authentication methods used by WebDAV? If so what are those methods? I'd be grateful for any help and insight into this problem! Many thanks, Mark