Your Myspace username/password can be directly read from..

Code:
/private/var/mobile/Applications/random string/library/preferences/com.myspace.iphone.plist
The "random string" on my phone begins with 8EF01D87. Your mileage may vary.

Just SSH into your phone, navigate to the folder and open the file with a text editor.

I can hardly believe that this slipped through Apples stringent app approval process.

You have been warned.