int imap_append(int imap_stream, string mbox, string message, stringflags);Returns true on sucess, false on error.
imap_append() appends a string message to the specified mailbox mbox. If the optional flags is specified, writes the flags to that mailbox also.
When talking to the Cyrus IMAP server, you must use "\r\n" as your end-of-line terminator instead of "\n" or the operation will fail.