Long story short
Is there an official, un-deprecated timezone that PHP5 recognizes for Eastern STANDARD time--not Eastern DAYLIGHT time?
America/New_York does observe DST and is the recommended timezone. (I went to a conference last year where Derick Rethans, who wrote a lot of the date/time code, spoke.) The idea behind the regional timezones is that they obey the timezone rules for the city/region they denote (which is why there are like 7 Indiana timezones).