Ok so this deals with the new multiple alert feature that was added in 2.1.
I always thought you had to actually unlock your iphone to prevent the additional alerts. But I had started to notice that it didn't always sound the extra alerts.
Maybe I am slow but I just NOW tested and realized that if you press a single button after you receive an SMS (whether you are lighting up the screen to read it, or even sleeping the iphone immediately following an SMS) you will NOT receive the additional alerts.
and to think I have been spending all this time unlocking my iphone... such a waste


I always thought you had to actually unlock your iphone to prevent the additional alerts. But I had started to notice that it didn't always sound the extra alerts.
Maybe I am slow but I just NOW tested and realized that if you press a single button after you receive an SMS (whether you are lighting up the screen to read it, or even sleeping the iphone immediately following an SMS) you will NOT receive the additional alerts.
and to think I have been spending all this time unlocking my iphone... such a waste