chkuser for qmail/netqmail > 1.0.3 and vpopmail > 5.3.x

Author: Antonio Nati tonix@interazioni.it

All rights on this software and
the identifying words chkusr and chkuser kept by the author

This software may be freely used, modified and distributed,
but this lines must be kept in every original or derived version.

Original author "Antonio Nati" and the web URL
"http://www.interazioni.it/opensource"
must be indicated in every related work or web page