[Zope] Adding Members en mass

Hi all I want to add LARGE number of members to my CMF site in one shot. The necessary dettils like login, password, domains and roles should be put in a file all the members should appear in the acl_users. What is the best way of doing this ? I am not looking at the possibility of adding this to a SQL DB about which I have no doubts. TIA. Regards, Chetan