hi, i need your help, i need to know i can change or populate an alert window popup with javascript.

as you can see from my image above, i have a script which populates a pop up window using javascript but if you also notice at the top, the title of it says: the page at http://www.wallpapera.com... so how can i change that to something else. this will help my users identify the popup. i have firefox mozilla and internet explorer EI does it matter which browser i am using?