Index: Doc/library/imaplib.rst
===================================================================
--- Doc/library/imaplib.rst	(revision 88061)
+++ Doc/library/imaplib.rst	(working copy)
@@ -84,8 +84,8 @@
 
 .. function:: Internaldate2tuple(datestr)
 
-   Converts an IMAP4 INTERNALDATE string to Coordinated Universal Time. Returns a
-   :mod:`time` module tuple.
+   Converts an IMAP4 INTERNALDATE string to local time.
+   Returns a :mod:`time` module tuple.
 
 
 .. function:: Int2AP(num)
@@ -101,7 +101,8 @@
 
 .. function:: Time2Internaldate(date_time)
 
-   Converts a :mod:`time` module tuple to an IMAP4 ``INTERNALDATE`` representation.
+   Converts a :mod:`time` module tuple (local time) to an
+   IMAP4 ``INTERNALDATE`` representation.
    Returns a string in the form: ``"DD-Mmm-YYYY HH:MM:SS +HHMM"`` (including
    double-quotes).
 
Index: Lib/imaplib.py
===================================================================
--- Lib/imaplib.py	(revision 88061)
+++ Lib/imaplib.py	(working copy)
@@ -22,7 +22,7 @@
 
 __version__ = "2.58"
 
-import binascii, errno, random, re, socket, subprocess, sys, time
+import binascii, errno, random, re, socket, subprocess, sys, time, calendar
 
 __all__ = ["IMAP4", "IMAP4_stream", "Internaldate2tuple",
            "Int2AP", "ParseFlags", "Time2Internaldate"]
@@ -1321,7 +1321,7 @@
         'Jul': 7, 'Aug': 8, 'Sep': 9, 'Oct': 10, 'Nov': 11, 'Dec': 12}
 
 def Internaldate2tuple(resp):
-    """Convert IMAP4 INTERNALDATE to UT.
+    """Convert IMAP4 INTERNALDATE to local time.
 
     Returns Python time module tuple.
     """
@@ -1348,22 +1348,12 @@
         zone = -zone
 
     tt = (year, mon, day, hour, min, sec, -1, -1, -1)
+    utc = calendar.timegm(tt) - zone
 
-    utc = time.mktime(tt)
+    return time.localtime(utc)
 
-    # Following is necessary because the time module has no 'mkgmtime'.
-    # 'mktime' assumes arg in local timezone, so adds timezone/altzone.
 
-    lt = time.localtime(utc)
-    if time.daylight and lt[-1]:
-        zone = zone + time.altzone
-    else:
-        zone = zone + time.timezone
 
-    return time.localtime(utc - zone)
-
-
-
 def Int2AP(num):
 
     """Convert integer to A-P string representation."""
@@ -1390,7 +1380,7 @@
 
 def Time2Internaldate(date_time):
 
-    """Convert 'date_time' to IMAP4 INTERNALDATE representation.
+    """Convert 'date_time' (local time) to IMAP4 INTERNALDATE representation.
 
     Return string in form: '"DD-Mmm-YYYY HH:MM:SS +HHMM"'
     """