function validation(thisform){
	if(thisform.namefield.value==''){
		alert("Please write your name!");
		return false;
		}
	if(thisform.emailfield.value==''){
		alert("Please enter a valid email id!");
		return false;
		}
	if(thisform.commentfield.value==''){
		alert("Please write your valuable comment!");
		return false;
		}
	
	thisform.submit();
}