MS has released an article saying that the following are compatible with SQL Server 2008
-NAV 4.0 SP3
-NAV 5.0
-NAV 2009
For further details you go through the following link
https://mbs.microsoft.com/knowledgebase/KBDisplay.aspx?SMNWUKNTMMYSZRRNOTTUKOOSTLLQWZYKKWSKRLPNMRUWVVUYLUPXPMVQRNR
https://mbs.microsoft.com/knowledgebase/KBDisplay.aspx?scid=kb;en-us;940718
