I have an AMD FirePro 2270 with the latest drivers supporting OpenGL 4.2. I am getting the following GLSL compile error when I try using multisample images:

ERROR: 0:8: error(#374) Multisample image is not supported on this ASIC

Here is my code:

Code :
#version 420
uniform layout(rgba8) image2DMS ColorImage;
void main(void)
  ivec2 coords = ivec2(gl_FragCoord.xy);
  vec4 color = imageLoad(ColorImage, coords, gl_SampleID);

The error is on the imageLoad line. Apparently, even though the AMD FirePro 2270 supports OpenGL 4.2, it doesn't support multisampled images. Does anyone know which FirePro cards have support for multisampled images?