Sputnik Games has posted a script on their blog that will let game developers for the iPhone and iPod Touch build games that can play sound effects from their game while at the same time play music from the iPod:

It seems that a lot of games on the iPhone and iPod touch do not let you listen to your music AND play the games sound effects at the same time. You either have to turn the sound off in the prefs to listen to music or the music simply fades out when the game starts.  Not ideal right?  I know, my first three games killed the the iPod music.  The good news is that Apple provides a way for both the iPod music and iPhone game sounds to mix in real time.

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