Teleconverter fitting problem

I have a Sigma T/C 1.4xEX DG which has been sitting happily on a Sigma 100-300.
I have just tried fitting it to a Sigma 50mm 1:2.8 DG Macro but cannot get it to fit. Both fit the camera

Is it me or the lens?

Sigma TCs are known to be fussy about which lenses they will fit. There is a useful compatibility chart published by Sigma link

It's you.

The rear of the macro is not recessed enough for the slightly protruding front element of the teleconverter to fit into.

Thanks helios, mine is not listed. So i guess that answers that.
Useful link saved to favourites.

Annoyingly very limited fits for Pentax.