floating point color buffer is not initialized

[Ehsan Kamrani]

My implementation supports GL_ARB_color_buffer_float, But I get an error when I request a floating point color buffer

if( GLEW_ARB_color_buffer_float )
{
CFloat fAttributes[] = {0,0};
UINT numFormats;
CInt attributes[] = {
WGL_DRAW_TO_WINDOW_ARB,GL_TRUE,
WGL_SUPPORT_OPENGL_ARB,GL_TRUE,
WGL_ACCELERATION_ARB,WGL_FULL_ACCELERATION_ARB,
WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_FLOAT_ARB,
WGL_DOUBLE_BUFFER_ARB,GL_TRUE,
0,0
};
wglChoosePixelFormatARB( m_pDC->GetSafeHdc(), attributes, fAttributes, 1, &PixelFormat, &numFormats );
if( numFormats == 0 )
{
//MessageBox
//return 0;
}

Note that if I replace WGL_TYPE_RGBA_FLOAT_ARB with WGL_TYPE_RGBA_ARB, I get no error.