function validateForm(thisform,varUrl){
	if(thisform.ename.value.length==0 && thisform.ename.value==""){
		alert("Silakan Isi Nama Anda!!!");
		thisform.ename.focus();
		return false;	
	}else if(thisform.epost.value.length==0 && thisform.epost.value==""){
		alert("Please insert email!!!");
		thisform.epost.focus();	
		return false;
	}else if(thisform.pesan_f.value.length==0 && thisform.pesan_f.value==""){
		alert("Please insert Comment!!!");
		thisform.pesan_f.focus();
		return;
		return false;		
	}else if(thisform.number.value.length==0 && thisform.number.value==""){
		alert("Please insert Security Code!!!");
		thisform.number.focus();	
	}else{
		thisform.submit();
		}
}

<script language='javascript'>
function cek_form(form){
if (form.ename.value == "") {
window.alert("Silakan Isi Nama Anda!!!");
form.ename.focus();
return false;
}
if (form.password.value == "") {
window.alert("Passwordnya mana?");
form.email.focus();
return false;
}
}
</script>