string imap_body (int imap_stream, int msg_number [, int flags])
imap_body() returns the body of the message, numbered msg_number in the current mailbox. The optional flags are a bit mask with one or more of the following:
FT_UID - The msgno is a UID
FT_PEEK - Do not set the \Seen flag if not already set
FT_INTERNAL - The return string is in internal format, will not canonicalize to CRLF.