Dose overrule Really support ObjectArx2010?I Got a link error on Arx2010

   I made a Arx program which used overrule mechanism on ObjectArx 2010.I wanted to change the drawing effect about Acdbpoint, so I wrote a class derived from AcGiDrawableOverrule,and overrided the function worldraw().My main codes look just as follow: 

//////header file ////////////////////////////////// 
class DrawOverrule : public AcGiDrawableOverrule 
{ 
public: 
    ACRX_DECLARE_MEMBERS(DrawOverrule); 
... 
    virtual bool isApplicable(const AcRxObject* pOverruledSubject) const; 
    virtual  Adesk::Boolean worldDraw(AcGiDrawable* pSubject, AcGiWorldDraw * wd); 
} 

//////cpp file ///////////////////////////////////// 
ACRX_CONS_DEFINE_MEMBERS(DrawOverrule,AcGiDrawableOverrule,0) 

Adesk::Boolean DrawOverrule::worldDraw( AcGiDrawable* pSubject, AcGiWorldDraw * wd ) 
{ 
//do something 
    return Adesk::kTrue; 
} 

bool DrawOverrule::isApplicable( const AcRxObject* pOverruledSubject ) const 
{ 
    return true; 
} 
///////////////////////////////////////////////////// 

         
       When I compiled and builded the project,a link error occured. 

       acrxEntryPoint.obj : error LNK2001:  unresolved external symbol "public: virtual class AcRxClass * __cdecl AcRxOverrule::isA(void)const " (?isA@AcRxOverrule@@UEBAPEAVAcRxClass@@XZ) 

        AcRxOverrule::isA()? It is Internal class which is offered by objectarx sdk,not my own class.I checked my configure on lib path, it is just all ok.If I made a project without anything refer to overrule mechanism,no error occur. More surprisingly,when I change my lib link to objectArx2012,that link error about AcRxOverrule::isA() will not occur,the compiler wil made success. 

      I guess that there may be some mistake in released objectarx2010,which I'm not very sure.Anybody else ever met similar problem?

      Thanks very much.