AS regards db, you likely want the later version.
IIRC, the API doesn't change within 3.x (I think).
I know several fixes/tunings/enhancements happen within
the version - things should never break BACKWARDS.

So try building against the current stable db3.

DB4 is a little too new for me and has a different API
(and several big boosts for certain uses, but use 3).

If that utterly fails, try db-3.1.17 (it should have
some changeable variation in pkgsrc.
Quoting Al Urbaitis (avu@lanl.gov):
> Hello All
> I am trying to use Ximian Exolution 1.0.8. 
> I am having trouble getting functions
> like the calendar and contact list to work.
> 
> These functions seem to depend on a particular
> version of Sleepy Cats libdb to work 
> (db-3.1.17)
> 
> It seems I don't have any version of this library
> installed and so I had a look at the available
> packages.I came across db-3 and db-4 but with
> much different version numbers (db3-3.11.2)
> 
> It seems the right version is here...
> http://www.sleepycat.com/update/snapshot/db-3.1.17.tar.gz
> 
> I need a little help with strategy here...
> I am under the impression I have to build Ximian from 
> source and some how integrate db-3.1.17.
> 
> Might someone help me with the correct recipe ?