Set another url link for my submenu?

1 

function generateMenu() {
	// setup the clips in array
	for (var i = 0; i<=numClips; i++) {
		// get reference to clip
		var clip = this["menuItem"+i];
		switch (i) {
		....
		case 3 :
			... 
			break;
		case 4 :
			clip.th = 100;
			clip.nav.menuText.text = "Nav 4"; 
			clip.gotoURL = "4";
			clip.menuItem1sub0.menuText.text = "Nav 4 A";
			clip.menuItem1sub0.gotoURL = "/4a";
			clip.menuItem1sub1.menuText.text = "Nav 4 B";
			clip.menuItem1sub1.gotoURL = "/4b";
			break;
etc.
clip.onRelease = goto;
		clip.onRollOver = over;
}}

function goto() {
trace(this.gotoURL);
}

Now it only traces 4 and not /4a or /4b???

How can i fix this?