Protect add for dup key in positional insert case.
Protect add for dup key in positional insert case.

jonnybee/csla,jonnybee/csla,MarimerLLC/csla,JasonBock/csla,JasonBock/csla,rockfordlhotka/csla,rockfordlhotka/csla,ronnymgm/csla-light,ronnymgm/csla-light,BrettJaner/csla,jonnybee/csla,rockfordlhotka/csla,MarimerLLC/csla,ronnymgm/csla-light,MarimerLLC/csla,JasonBock/csla,BrettJaner/csla,BrettJaner/csla