Checking the version

[osiris@cs.utexas.edu]

I have some code that worked with the prevoius version of MCL along with a
number of other platforms by using conditional inclusion.  For mcl specific
code #+:ccl was used.  However, now I want to add support for the new
version (ie using the new CLOS classes) without killing the support of the
old version.  Is there a #+XXXX that will work to diferentiate between the
old and new versions?  What is the right way to do this?

Thanks.