/**
 * get elements of a page by their class name.
 * sourced from http://www.robertnyman.com/2005/11/07/the-ultimate-getelementsbyclassname/
 */

function getElementsByClassName(className, tag, elm){
	var testClass = new RegExp("(^|\\\\s)" + className + "(\\\\s|$)");
	var tag = tag || "*";
	var elm = elm || document;
	var elements = (tag == "*" && elm.all)? elm.all : elm.getElementsByTagName(tag);
	var returnElements = [];
	var current;
	var length = elements.length;
	for(var i=0; i<length; i++){
		current = elements[i];
		if(testClass.test(current.className)){
			returnElements.push(current);
		}
	}
	return returnElements;
}