version 	date
1.0 	July 16, 1993
1.1.0 	November 5, 1993
1.1.2 	February 5, 1994
2.0 	July 2, 1994
2.1 	October 31, 1994
2.2 	March 30, 1995
2.3 	May 24, 1995
3.0 	November 30, 1995
3.1 	June 3, 1996
3.2 	February 17, 1997
3.3 	June 11, 1997
3.4 	October 14, 1997
3.5 	June 9, 1998
3.6 	October 28, 1998
3.9 	May 10, 1999
4.0 	May 17, 1999
7.0 	October 25, 1999
7.1 	June 22, 2000
8.0 	July 1, 2001
8.1 	June 18, 2002
9.0 	March 19, 2003
9.1 	September 26, 2003
10.0 	June 23, 2004
10.1 	February 2, 2005
10.2 	September 14, 2005
11.0 	October 2, 2006
12.0 	July 1, 2007
12.1 	May 2, 2008
12.2 	December 10, 2008
13.0 	August 26, 2009
13.1 	May 24, 2010