function echeck(str) {

		var at="@"
		var dot="."
		var lat=str.indexOf(at)
		var lstr=str.length
		var ldot=str.indexOf(dot)
		if (str.indexOf(at)==-1){
		   alert("Please enter a valid email address")
		   return false
		}

		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		   alert("Please enter a valid email address")
		   return false
		}

		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		    alert("Please enter a valid email address")
		    return false
		}

		 if (str.indexOf(at,(lat+1))!=-1){
		    alert("Please enter a valid email address")
		    return false
		 }

		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		    alert("Please enter a valid email address")
		    return false
		 }

		 if (str.indexOf(dot,(lat+2))==-1){
		    alert("Please enter a valid email address")
		    return false
		 }
		
		 if (str.indexOf(" ")!=-1){
		    alert("Please enter a valid email address")
		    return false
		 }
 		 return true					
	}
<!--

function validate_form ( )
{
    valid = true;
	var emailID=document.VIP_form.elements["Cemail"]

    if ( document.VIP_form.elements["Cname"].value == "" )
    {
        alert ( "Please fill in your Name" );
        valid = false;
    }
	else if ((emailID.value==null)||(emailID.value=="")){
		alert("Please Enter your Email Address")
		emailID.focus();
		valid = false;
	}
	else if (echeck(emailID.value)==false){
		emailID.value=""
		emailID.focus();
		valid = false;
	}
    return valid;
	
}