function ClassTester(className)
{
    this.regex = new RegExp("(^|\\s)" + className + "(\\s|$)");
}

ClassTester.prototype.isMatch = function(element)
{
    return this.regex.test(element.className);
}

function rewriteLinks() {
	var links = document.getElementsByTagName('a');
	var tester = new ClassTester('new');
	
	for(var i = 0; i < links.length; i++) {
		if(tester.isMatch(links[i])) {
			links[i].target = '_blank';
		}
	}
}

window.onload = function() {
	rewriteLinks();
}