| 2.1 | 2.0+1.6.1 | 2001 | 
 | PSF | no | 
| 2.0.1 | 2.0+1.6.1 2001 | 
 | PSF | yes | |
| 2.1.1 | 2.1+2.0.1 | 2001 | PSF | yes | |
| 2.2 | 2.1.1 | 2001 | PSF | yes | |
| 2.1.2 | 2.1.1 | 2002 | PSF | yes | |
| 2.1.3 | 2.1.2 | 2002 | PSF | yes | |
| 2.2.1 | 2.2 | 2002 | PSF | yes | |
| 2.2.2 | 2.2.1 | 2002 | PSF | yes | |
| 2.2.3 | 2.2.2 | 2003 | PSF | yes | |
| 2.3 | 2.2.2 | PSF | yes | ||
| 2.3.1 | 2.3 | PSF | yes | ||
| 2.3.2 | 2.3.1 | PSF | yes | ||
| 2.3.3 | 2.3.2 | PSF | yes | ||
| 2.3.4 | 2.3.3 | 2004 | PSF | yes | |
| 2.3.5 | 2.3.4 | 2005 | PSF | yes | |
| 2.4 | 2.3 | 2004 | PSF | yes | |
| 2.4.1 | 2.4 | 2005 | PSF | yes | |
| 2.4.2 | 2.4.1 | 2005 | PSF | yes | |
| 2.4.3 | 2.4.2 | 2006 | 
 | PSF | yes | 
| 2.4.4 | 2.4.3 | 2006 | 
 | PSF | yes | 
| 2.5 | 2.4 | 2006 | PSF | yes | |
| 2.5.1 | 2.5 | 2007 | PSF | yes | |
| 2.5.2 | 2.5.1 | 2008 | PSF | yes | |
| 2.5.3 | 2.5.2 | 2008 | PSF | yes | |
| 2.6 | 2.5 | 2008 | PSF | yes | |
| 2.6.1 | 2.6 | 2008 | PSF | yes | |
| 2.6.2 | 2.6.1 | 2009 | PSF | yes | |
| 2.6.3 | 2.6.2 | 2009 | 
 | PSF | yes | 
| 2.6.4 | 2.6.3 | 2009 | 
 | PSF | yes | 
| 2.6.5 | 2.6.4 | 2010 | PSF | yes | |
Footnotes:
(1)
a modified version without making your changes open source. The 
