function showMenu(theMenu){
	alreadyOpen = 0;
	Move = false;
	offset = Number(getOffset(theMenu));
	oldoffset = 0;
	for(i=1;i<6;i++){
		nameOfMenu = 'menu'+i+'_b';
		if (document.all[nameOfMenu].style.visibility == 'visible'){
			alreadyOpen = i;
			oldoffset = Number(getOffset(nameOfMenu));
			resetMenu(nameOfMenu,oldoffset);
		}
	}
	index=getIndex(theMenu);
	if (alreadyOpen != index )
		resetMenu(theMenu,offset);
	return true;
}
/* ********************************************************************************** */	
	
	//returns the index of the menu
	function getIndex(theMenu){
		index= theMenu.indexOf("_");
		theNum=Number(theMenu.substring(4,index));
		return theNum;
	}

/* ********************************************************************************** */
	//returns the other menu with the same name
function getOther(theString){
	index= theString.indexOf("_a");
	if (index != -1)
		return theString.substring(0,index)+"_b";
	index= theString.indexOf("_b");
	if (index != -1)
		return theString.substring(0,index)+"_a";
}
/* ********************************************************************************** */

	function getOffset(mymenu){
		//alert('getoffset of '+mymenu);
		offset1 = 6;
		indice = 0;
		index= mymenu.indexOf("_");
		newMenu = mymenu.substring(0,index)+"_b";
		for (i=0;i<document.images.length;i++){
			if (document.images[i].name == newMenu+'_1'){
				indice=i;
				break;
			}
		}
		
		for (i=indice;i<(indice+20);i++){
			if (document.images[i].name.indexOf(newMenu) != -1)
				offset1+=19;
			else
				break;
		}
		//alert('calculated offset'+offset1)
		return offset1;
	}
	
/* ********************************************************************************** */
	//opens or closes the menu and shifts the subsequent menus	
	function resetMenu(theMenu,offset){
		menu1=getOther(theMenu);
		document.all[menu1].style.visibility='visible';
		document.all[theMenu].style.visibility='hidden';
		isOpen = theMenu.indexOf("_b")== -1?1:0; 
		
		nextIndex = getIndex(theMenu)+1;
		
		for(i=nextIndex;i<6;i++){
			nextMenu='menu'+i+'_a';
			oldPos = document.all[nextMenu].style.top;
			oldPos = oldPos.substring(0,oldPos.indexOf("px"));
			oldPosNum = Number(oldPos);
			newPosNum = 0;
			//alert('reset'+i+' offset '+offset);
			if (isOpen == 1)
				newPosNum = oldPosNum+(offset);
			else
				newPosNum = oldPosNum-(offset);
			document.all[nextMenu].style.top=newPosNum+"px";
		}
	 }