nl2br in Javascript

Code:
function nl2br (str, is_xhtml) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: Philip Peterson
    // +   improved by: Onno Marsman
    // +   improved by: Atli Þór
    // +   bugfixed by: Onno Marsman
    // *     example 1: nl2br('Kevin\nvan\nZonneveld');
    // *     returns 1: 'Kevin<br />\nvan<br />\nZonneveld'
    // *     example 2: nl2br("\nOne\nTwo\n\nThree\n", false);
    // *     returns 2: '<br>\nOne<br>\nTwo<br>\n<br>\nThree<br>\n'
    // *     example 3: nl2br("\nOne\nTwo\n\nThree\n", true);
    // *     returns 3: '<br />\nOne<br />\nTwo<br />\n<br />\nThree<br />\n'
 
    breakTag = '<br />';
    if (typeof is_xhtml != 'undefined' && !is_xhtml) {
        breakTag = '<br>';
    }
 
    return (str + '').replace(/([^>]?)\n/g, '$1'+ breakTag +'\n');
}
http://kevin.vanzonneveld.net/techbl...or_phps_nl2br/