function prependChild(parent, node) {
    parent.insertBefore(node, parent.firstChild);
}

function require(node, errormsg, errorlist, err){
	node.value = Trim(node.value);
	if(node.value == ''){
		var errorElement = document.createElement('li');
		var errorText = document.createTextNode(errormsg);
		errorElement.appendChild(errorText);
		prependChild(errorlist, errorElement);
		node.focus();
		return (err+1);
	}else{
		return (err);
	}
}

function checkEmail(addr){
	addr = Trim(addr);
	var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
	var emailPat=/^(.+)@(.+)$/;
	var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
	var validChars="\[^\\s" + specialChars + "\]";
	var quotedUser="(\"[^\"]*\")";
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
	var atom=validChars + '+';
	var word="(" + atom + "|" + quotedUser + ")";
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");
	
	var matchArray=addr.match(emailPat);

	if (matchArray==null) {
		return false;
	}
	
	var user=matchArray[1];
	var domain=matchArray[2];

	for (i=0; i<user.length; i++) {
		if (user.charCodeAt(i)>127) {
			return false;
   		}
	}
	for (i=0; i<domain.length; i++) {
		if (domain.charCodeAt(i)>127) {
			return false;
   		}
	}
	if (user.match(userPat)==null) {
		return false;
	}
	
	var IPArray=domain.match(ipDomainPat);
	if (IPArray!=null) {
		for (var i=1;i<=4;i++) {
			if (IPArray[i]>255) {
				return false;
   			}
		}
	return true;
	}

	var atomPat=new RegExp("^" + atom + "$");
	var domArr=domain.split(".");
	var len=domArr.length;
	
	for (i=0;i<len;i++) {
		if (domArr[i].search(atomPat)==-1) {
			return false;
   		}
	}

	if (domArr[domArr.length-1].length!=2 && 
			domArr[domArr.length-1].search(knownDomsPat)==-1) {
		return false;
	}

	if (len<2) {
		return false;
	}
return true;
}

function Trim(TRIM_VALUE){
if(TRIM_VALUE.length < 1){
return"";
}
TRIM_VALUE = RTrim(TRIM_VALUE);
TRIM_VALUE = LTrim(TRIM_VALUE);
if(TRIM_VALUE==""){
return "";
}
else{
return TRIM_VALUE;
}
} //End Function

function RTrim(VALUE){
var w_space = String.fromCharCode(32);
var v_length = VALUE.length;
var strTemp = "";
if(v_length < 0){
return"";
}
var iTemp = v_length -1;

while(iTemp > -1){
if(VALUE.charAt(iTemp) == w_space){
}
else{
strTemp = VALUE.substring(0,iTemp +1);
break;
}
iTemp = iTemp-1;

} //End While
return strTemp;

} //End Function

function LTrim(VALUE){
var w_space = String.fromCharCode(32);
if(v_length < 1){
return"";
}
var v_length = VALUE.length;
var strTemp = "";

var iTemp = 0;

while(iTemp < v_length){
if(VALUE.charAt(iTemp) == w_space){
}
else{
strTemp = VALUE.substring(iTemp,v_length);
break;
}
iTemp = iTemp + 1;
} //End While
return strTemp;
} //End Function