Jazzdude
The new chip can be installed in old models, I know because I have done it. In fact if you look up on tnt-audio Geoff Husband describes doing exactly that in his review of the ekianthus. With regards to the new module, as I recall (but can't be positive) it is easy enough to tell the difference between the two, the problem is you have to gain access to the chip which is quite well hidden. If it is an X I believe it must have the new chip, since that was how they designated. M. lurne is generally quite good about answering but if you have questions the us distributor is I believe Aberdeen components and this should give you the link.
http://show.audiogon.com/cgi-bin/shm.pl?dgtlconv&1046233054&item&Chichiuno&4&5&6&http://cgi.audiogon.com/cgi-bin/fs_srch.plQQANYAAAApurlsrchAAEXYAAstAAAAAAaudiomeca
Drop me a note if you have questions and good luck
Gary