[Zope] LoginManager with SQL and Skinscript: adding properties to propertysheet propertysheet

Hi all, I am following Dan Pierson's How-To SQL LoginManager with SQL and Skinscript. I am not able to add properties. I created LoginManager:LoginUser subclassed zclass def for a user with a propertysheet Basic. It had properties password and email. The LM methods I tested failed so I deleted the properties. Now I want to add them again. When I try I get: for password Invalid property id, password. It is in use. for email: Invalid property id, email. It is in use. I also deleted the entire propertysheet and tried to add the props but the same error occured. I can add new props but not ones that were deleted earlier. Is there a way around this problem? Zope 2.2.1 System Platform: freebsd4 -Aaron