From syslog-ng 1.53 you could use the template option...(but there is no month in Short English Form...) like this
 
destination example { file("/var/log/example.log" template("$MONTH $DAY $YEAR $HOUR:$MIN:$SEC $MESSAGE")); };
 
(Read this post : https://lists.balabit.hu/pipermail/syslog-ng/2001-January/001153.html to understand template option)
 
Amodiovalerio [Hypo] Verde
----- Original Message -----
From: Zhou, Tao (Tao)
To: syslog-ng@lists.balabit.hu
Sent: Thursday, September 18, 2003 4:58 AM
Subject: [syslog-ng]Year in the log

Is there a way for syslog-ng to include year in a logged message? For example,

Sep 17 2003 20:00:00 ...

Thanks.

Tao Zhou