Repeat Password Checker

I'm making the register form to add user in my system. I want user to type fullname,username, password & repeat password. So I write function to check the input from users.This is one of the part in function

else if(form.pwd2.value <> form.pwd1.value){
alert("Repeat password again!")
form.pwd2.focus();
return(false);
}

This part are giving error when submit clicked. So i cut this part & try again & it's ok & no error. i want to make this repeat password checker.