opengl.cpp
find this: Code:
void APIENTRY pglBegin

somewhere in body add following: Code:
if(cvar.wiremodel && mode != GL_POLYGON && (mode==GL_TRIANGLES||mode==GL_TRIANGLE_STRIP||mode==GL_TRIANGLE_FAN))
  {
      glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
      glLineWidth(2);

  } else {
      glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
  }

Register your cvars!