I know I'm late with this suggestion but would it not be possible to simply replace the ".7RC" suffix by ".6-", like in the following table:
Date
Version
2008/12/30
2.0.1.7RC3
2.0.1.6-3
2008/12/31
2.0.1.7RC4
2.0.1.6-4
2009/01/09
2.0.1.7RC5
2.0.1.6-5
2009/01/14
2.0.1.7RC6
2.0.1.6-6
2009/01/20
2.0.1.7RC7
2.0.1.6-7
2009/02/28
2.0.1.7RC8
2.0.1.6-8
2009/03/14
2.0.1.7RC9
2.0.1.6-9
2009/03/26
2.0.1.7RC9a
2.0.1.6-9a
2009/06/10
2.0.1.7.RC9c
2.0.1.6-9c
2009/10/01
2.0.1.6 (rev.2009.10.01)
2.0.1.6-10
2009/10/05
2.0.1.6 (rev.2009.10.05)
2.0.1.6-11