I'm using php 4.0.5 with iPlanet 4.1 and Solaris 7. THe simple PHP Authentication script, that works on the same machine with Apache does not work with iPlanet:

if(!isset($PHP_AUTH_USER)) {
    Header("WWW-Authenticate: Basic realm=\"My Realm\"");
    Header("HTTP/1.0 401 Unauthorized");
    echo "Enter User Name\n";
    exit;
  } else {
	if(!isset($PHP_AUTH_PW)) {
    	Header("WWW-Authenticate: Basic realm=\"My Realm\"");
	    Header("HTTP/1.0 401 Unauthorized");
    	echo "Enter password\n";
	    exit;
	} else {
  		if (($PHP_AUTH_USER!="user") || ($PHP_AUTH_PW!="password")) {
				Header("WWW-Authenticate: Basic realm=\"My Realm\"");
    			Header("HTTP/1.0 401 Unauthorized");
	    		echo "Not authorized\n";
    			exit;
		}		
	}	
  }

It acts as if "Cancel" is pressed. PHP_AUTH_USER and PHP_AUTH_PW are not set after pressing "OK" button. I looked into $HTTP_SERVER_VARS array there is no HTTP_AUTH_USER or PHP_AUTH_USER there.