edit mobilephone.app files

[midniter]

edit mobilephone.app files
when i make phone call i see this screen ...see below

http://farm4.static.flickr.com/3497/4000637154_a2bb93a763.jpg

when i call someone and press the "speaker" button it does not change color
so i dont know if speaker is on or off
the other buttons in this pic also do not change when pressed

i want to know to make them change when 'pressed'
thanks...