5322 => 'Internet message format (2008)',
3501 => 'IMAP4rev1',
2177 => 'IMAP IDLE',
+ 2683 => 'IMAP4 Implementation Recommendations',
# 5032 = 'WITHIN search extension for IMAP',
4978 => 'IMAP COMPRESS Extension',
# 5182 = 'IMAP Extension for Referencing the Last SEARCH Result',