The Passcode Lock feature in Apple iPhone OS 1.0 through 2.1 and iPhone OS for iPod touch 1.1 through 2.1 displays SMS messages when the emergency-call screen is visible, which allows physically proximate attackers to obtain sensitive information by reading these messages. NOTE: this might be a duplicate of CVE-2008-4593.
http://www.vupen.com/english/advisories/2008/3232
http://www.securityfocus.com/bid/32394
http://support.apple.com/kb/HT3318
http://secunia.com/advisories/32756
http://lists.apple.com/archives/security-announce/2008/Nov/msg00002.html