diff -r 26200f535296 Lib/imaplib.py
--- a/Lib/imaplib.py	Wed Oct 03 13:53:28 2012 +0530
+++ b/Lib/imaplib.py	Wed Oct 03 15:55:26 2012 +0200
@@ -22,7 +22,7 @@
 
 __version__ = "2.58"
 
-import binascii, errno, random, re, socket, subprocess, sys, time, calendar
+import binascii, errno, random, re, socket, subprocess, sys, time, calendar, select
 from datetime import datetime, timezone, timedelta
 try:
     import ssl
@@ -61,6 +61,7 @@
         'GETANNOTATION':('AUTH', 'SELECTED'),
         'GETQUOTA':     ('AUTH', 'SELECTED'),
         'GETQUOTAROOT': ('AUTH', 'SELECTED'),
+        'IDLE':         ('AUTH', 'SELECTED'),
         'MYRIGHTS':     ('AUTH', 'SELECTED'),
         'LIST':         ('AUTH', 'SELECTED'),
         'LOGIN':        ('NONAUTH',),
@@ -813,6 +814,30 @@
         """
         return self._simple_command('UNSUBSCRIBE', mailbox)
 
+    def idle(self, timeout = 29 * 60):
+        """Implements IMAP IDLE extension as described in RFC 2177.
+
+        Waits until state of current mailbox changes.
+
+        Default timeout is the maximum possible idle time according to RFC 2177.
+
+        (typ, {data}) = <instance>.idle(timeout)
+
+        Returns dictionary of all untagged responses received while idling.
+        """
+        if not "IDLE" in self.capabilities:
+            raise self.error("server does not support IDLE command.")
+
+        self.untagged_responses = {}
+        tag = self._command("IDLE")
+        self._get_response() # read continuation response
+
+        select.select([self.sock],[],[],timeout)
+
+        self.send(b"DONE" + CRLF)
+        typ,data = self._command_complete("IDLE", tag)
+        return typ, self.untagged_responses
+
 
     def xatom(self, name, *args):
         """Allow simple extension commands