Does anyone know how to make sure JavaScript validation works in FireFox?

[ConfusedShark]

All I want the javascript to do is display an alert box saying a box has not had any data entered and the code is simple with below an example.

<script>
function validate()
{
if (myform.username.value=="")
{
alert("No User Name entered");
myform.username.focus();
return false;
}

if (myform.password.value=="")
{
alert("No Password entered");
myform.password.focus();
return false;
}

return true;
}
</script>

<form name ="myform" action= "checkpassword.asp" method= "post" onSubmit="return validate()">

Username: <input type= "text" name= "username" size="10">
Password:
<input type="password" name= "password" size="10">
<input type="submit" value= "Login">

</form>

It's simple code, Firefox has JavaScript enabled. I have also tested it in IE, Opera and Safari and they all display the alert box as intended when nothing entered

[Damasta]

Add "document" in front of myform.username.value. This is the culprit. The proper syntax is
document.formname.inputfield.value
To be safe try this:
add an id attribute to the tag for instance:

<input type="text" id="example" />

Now to refer to the data in there do:
document.getElementById('example').value

Also, try to save the input to a variable.

x=document.getElementById('example').value

Lastly for Firefox, get the extension called "FireBug". It allows you to troubleshoot JavaScript and HTML problems.