+ * This module is an SMTP and ESMTP implementation for the Citadel system.
+ * It is compliant with all of the following:
+ *
+ * RFC 821 - Simple Mail Transfer Protocol
+ * RFC 876 - Survey of SMTP Implementations
+ * RFC 1047 - Duplicate messages and SMTP
+ * RFC 1854 - command pipelining
+ * RFC 1869 - Extended Simple Mail Transfer Protocol
+ * RFC 1870 - SMTP Service Extension for Message Size Declaration
+ * RFC 1893 - Enhanced Mail System Status Codes
+ * RFC 2033 - Local Mail Transfer Protocol
+ * RFC 2034 - SMTP Service Extension for Returning Enhanced Error Codes
+ * RFC 2197 - SMTP Service Extension for Command Pipelining
+ * RFC 2487 - SMTP Service Extension for Secure SMTP over TLS
+ * RFC 2554 - SMTP Service Extension for Authentication
+ * RFC 2821 - Simple Mail Transfer Protocol
+ * RFC 2822 - Internet Message Format
+ * RFC 2920 - SMTP Service Extension for Command Pipelining