Strange Problem

When choosing "Go to Definition" on a method I only get the object browser appear which shows two identically named classes, with different methods.  I therefore cannot edit the one I need to.
According to the object browser both look like this:

Public Class DBAccess           Inherits System.Object      Member of: SesameDBAccessPublic Class DBAccess
          Inherits System.Object
     Member of: DBAccess
However one of the DBAccess namespaces has ...