* Check keys on import?
+ * Non self-signed user IDs
+ * Non self-signed subkeys
+ * Invalid revocations
+ * Signatures marked as non-exportable
+ * PKS subkey damage
* Better signature subpacket parsing (primary UID for example).
* Better merging of signatures; need to compare subpackets on Type 4 packets
and choose which we should use (how? most recent date?)