<script language="JavaScript1.2">

var highlightcolor="lightyellow"

var ns6=document.getElementById&&!document.all
var previous=''
var eventobj

//Regular expression to highlight only form elements
var intended=/INPUT|TEXTAREA|SELECT|OPTION/

//Function to check whether element clicked is form element
function checkel(which){
if (which.style&&intended.test(which.tagName)){
if (ns6&&eventobj.nodeType==3)
eventobj=eventobj.parentNode.parentNode
return true
}
else
return false
}

//Function to highlight form element
function highlight(e){
eventobj=ns6? e.target : event.srcElement
if (previous!=''){
if (checkel(previous))
previous.style.backgroundColor=''
previous=eventobj
if (checkel(eventobj))
eventobj.style.backgroundColor=highlightcolor
}
else{
if (checkel(eventobj))
eventobj.style.backgroundColor=highlightcolor
previous=eventobj
}
}

</script>

<FORM onKeyUp="highlight(event)" onClick="highlight(event)">
"
"
</FORM>