Thread: Inheritance problem, help please!

I am having this problem with inheritance:
I have a header file that defines my base class, called CRTBaseMesh

It looks like this:

PHP Code:

#ifndef RTBASEMESH_H_DEF
#define RTBASEMESH_H_DEF

#include "rtMD2.h"

class CRTBaseMesh
{
public:
    CRTBaseMesh();
    ...
   ......
private:

};
#endif 


Now this is the header file containing the class that inherits from that base cl,ass, header file:

PHP Code:

#ifndef RTMD2_H_DEF
#define RTMD2_H_DEF

#include "rModel.h" //the previous header file

class CRTMD2 : public CRTBaseMesh
{
    public:
    CRTMD2();
   ..
  ....
private:

};

#endif 


The problem is that it says that CRTBaseMesh: base class undefined.
As you see, I include the header containing the base class, what might be the catch here?