Iphone 4 message tones

I was wondering how to change the text message tone to a simple beep. There doesn't seem to be any in the sound setting lists. Any help on this would be appreciated.

In Settings > Sounds > Text Tone, you can choose from Tri-tone (the default, I think), Chime, Glass, Horn, Bell, and Electronic. No "beep", I know, but Bell is the shortest.

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Ios 5 has about 30 new tones in addition to those and will have a tone store in iTunes (and you can make your own as we do ring tones now)

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It's good to read that there will be more choice, and especially that we can make our own.

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I like the glass tone... it is a simple one note tone that sounds nice. I also like the chime one.