isnan/isinf not declared

[Graham Percival]

fink patches, OSX 10.3.9... but this is a new OS installation, so I 
might have
forgotten to install any required fink packages.  ./configure doesn't 
complain,
though.

Current CVS dies with:

-----
In file included from include/flower-proto.hh:22,
                 from include/string-handle.hh:12,
                 from include/string.hh:22,
                 from axis.cc:9:
include/real.hh:19: error: `isnan' not declared
include/real.hh:20: error: `isinf' not declared
make[1]: *** [out/axis.o] Error 1
make: *** [all] Error 2