19970817 code: The format of the virtualpopdomains file has changed: a field,
         'domain', has been prepended. This field contains the popdomain name,
         used (among others) by the virtual pophost support.
19970822 code: added '-d' flag to chkpoppass to make address testing easier.
         code: changed mkpopuser to use users/cdb instead of users/assign.
19970824 bug: mkpopuser wasn't setting ownership of user homedir correctly.
         code: fixed chkpoppass '-d' to enable qmail-pop3d to be run by
         changing the calling syntax.
19970912 code: added -s flag to mkpopuser to show users/cdb info on a user.
19971120 code: when TCPLOCALHOST is not set, chkpoppass now uses the first
         virtualpopdomains entry to determine the pop domain directory to use;
         this makes chkpoppass work when run from inetd.
19971127 doc: major tweaking and cleanup.
