var opera     = ( navigator.userAgent.indexOf( 'Opera' )     != -1 );
var konqueror = ( navigator.userAgent.indexOf( 'Konqueror' ) != -1 );
var safari    = ( navigator.userAgent.indexOf( 'Safari' )    != -1 );
var mozilla   = ( navigator.userAgent.indexOf( 'Gecko' )     != -1 && !safari && !konqueror);

var ie        = ( document.all && !opera );
var ie4       = ( ie && !document.getElementById );
var ie5x      = ( document.all && document.getElementById );
var ie5mac    = ( macintosh && ie5x );
var ie5xwin   = ( windows && ie5x );

var ns3       = ( navigator.appName == "Netscape" && (parseInt(navigator.appVersion)==3) ) ? true : false;
var ns4       = ( navigator.appName == "Netscape" && (parseInt(navigator.appVersion)==4) ) ? true : false;
var ns6       = ( document.getElementById && !document.all)? true : false;