Problems with Apple's Security Update 2011-005 (Lion)?
The update replaces 3 files, all pertaining to your system's keychain. They are as follows:

/System/Library/Keychains/EVRoots.plist
/System/Library/Keychains/SystemRootCertificates.keychain
/System/Library/Keychains/SystemTrustSettings.plist


It is impossible that the update has caused your problems. Look elsewhere.