From http://java.net/jira/browse/MACOSX_PORT-464 --
Even if the user KeyChain contains more than one certificate chain with private key the Keychain-based KeyStore implementation is only able to retrieve one single chain.
Step to reproduce:
(1) import 2 or more certificate with private keys in KeyChain (for instance from PKCS#12 files)
(2) list the entries with keytool:
keytool -list -provider apple.security.AppleProvider -storetype KeychainStore -keystore NONE | grep PrivateKeyEntry
(3) only one entry is printed