[Zope] Logging on as a delegate ?

Sorry if this is a duplicate posting. I have set up a subfolder from my main site and added an admin user (called pam) to its acl_user document. How should pam logon ? I thought one should attempt to go to http://my.zope.server:8080/Sub_Folder/manage Is this right ? But from there I can only logon as the super user. I have checked the acl_user, deleted and reinstated the user a couple of times. This is probably a very simple problem, but I just can't see it. Thanks in advance Keith