[jQuery] Problem with variable scope

[new_gmap]

Hi there, I have a quastion for you.

I am developing an application with PHP - JQuery - Google Map.

Here is the link:
http://www.nothingisclear.net/ndovadoIgnition/index.php/newTrip

You can see inside the source page, that I load several js into the
div="wrapper"

Inside newtrip.js i have a initialize two google map object outside
every function:

        $(document).ready(function(){

                var data = [];
                var fromMap = new GMap2(document.getElementById('fromMap'));
                var toMap = new GMap2(document.getElementById('toMap'));
                var geo = new GClientGeocoder();

                $("#fromLocation").focus(function(){
                        $("#fromMap").show();
                        loadGoogleMap("fromMap", fromMap);
                })


As you can see, I fire the loadGoogleMap function with two parameters:
the div name and the map object.
The loadGoogleMap is situated into the file gmap2.function.je that I
include into the document before the newtrip.js.

We decided to keep the function separated to reach a better code
quality.

My question is, why I have to pass the mapObject as a parameter of the
function?
indeed i have to pass it as a parameter becaouse of the it is nt
reachable!!!!

I this that if I declare the frommap object outside every function it
would be global for the page.

Am i wrong??