function MultiClass(classString) {
if (classString) {
var classes = String(classString).split(' ');
} else {
var classes = new Array();
}

this.addClass = function(className) {

if (!this.classExists(className)) {
classes.push(className);
return true;
} else {
return false;
}

}

this.removeClass = function(className) {
for (var i in classes) {
if (classes[i] == className) { classes.splice(i,1); }
}
}

this.classExists = function(className) {
for (var i in classes) {
if (classes[i] == className) { return true; }
}
return false;
}

this.importClasses = function(classList) {
classes = classes.concat(classList);
}

this.toString = function() {
var str = '';
var i = 0;
if (classes.length > 0) {
str += classes[i];
i++;
while (i < classes.length) {
str += ' ' + classes[i];
i++;
}

}
return str;
}

}