Fix typo

README

@@ -388,7 +388,7 @@ Reliant UNIX: The thread support does not compile on Reliant UNIX, and
         platform as well.  This should be resolved in time for a
         future release.
 
-MaxOS X:  You need to add the "-traditional-cpp" option to the
+MacOS X:  You need to add the "-traditional-cpp" option to the
         compiler command line for the MacOS X Public Beta.  This is
         appearantly a bug in the default pre-processor, and is
         expected not to be a problem with future versions.  Run