I've encountered this problem in 4.96, but generally only with a contact of 5,000+txt's But anyways, here's what happens :
I'll get a txt notification, ringer/vib and LED.
I'll see it in the pull down bar, can read some of it.
I'll tap the screen to view and POOF! it disappears, totally.
Idk what is causing this, but its a killer. ( I cant ask ppl to resend txt's over and over)