I'm seeing the dreaded "Code Sign error: The identity 'iPhone Developer' doesn't match any valid certificate/private key pair in the default keychain" error.

Strange, as it used to work. Not sure what changed.

A few of the symptoms I've noticed beyond this:

• In the project info, for Code Signing Identity, instead of saying "iPhone Developer: My Name Here", it only says "iPhone Developer", followed by a list of grayed out Provisioning Profiles with the error message "profile doesn't match any valid certificate/private key pair in the keychain."
• In the organizer, if I click the "Developer Profile" sidebar entry, it shows one entry in the "Identities" pane, "iPhone Distribution: My Name Here". However, no profiles show in the Provisioning Profiles pane.
• In the organizer, if I click the "Provisioning Profiles" sidebar entry, for each of the profiles there it reports "A valid signing identity matching this profile could not be found in your keychain."

I've tried a handful of the usual folk cures for this ailment, without success so far, such as:

• Cleared my old keypairs and expired developer identity cert out of the keychain.
• Deleted my old developer profile, created a new one, and regenerated the provisioning profile after.
• Reconfirmed: The App ID on the provisioning portal for this app is a pure wildcard ID. (The "Bundle Identifier" in the info.plist is just the appname, no reversed domain prefix.)
• Restored my iPhone.
• Overstalled the latest version of Xcode.