== Is the Eastern Time zone *always* GMT - 0500? == 

 I see that many mail servers (and computers) in the Eastern Time Zone are currently set to GMT - 0400 (4 hours offset from GMT). 

 This time-zone article does not mention if it's correct procedure to modify your system's GMT offset to account for (or correct for) DST  *or* if your GMT offset is *CONSTANT ALL YEAR* for your geographic location or zone? 

 WHAT IS THE ANSWER?