// reset classnames for two different elements //
function Z_showHide(idA, classNameA1, classNameA2, idB, classNameB1, classNameB2) {
	if (idA.className==classNameA1)
		idA.className=classNameA2; 
	else 
		idA.className=classNameA1;
	if (idB.className==classNameB1)	
		idB.className=classNameB2; 
	else 
		idB.className=classNameB1;
}