=== modified file 'startup/EpicsHostArch'
--- startup/EpicsHostArch	2010-10-14 19:01:40 +0000
+++ startup/EpicsHostArch	2011-06-27 20:02:10 +0000
@@ -39,7 +39,7 @@
         cpu=`uname -m`
         case "$cpu" in
             "Power Macintosh") cpu=ppc ;;
-            "i386") cpu=x86 ;;
+            "i386" | "x86_64" ) cpu=x86 ;;
         esac
         echo ${os}-${cpu}${suffix}
         ;;

=== modified file 'startup/EpicsHostArch.pl'
--- startup/EpicsHostArch.pl	2010-10-14 19:01:40 +0000
+++ startup/EpicsHostArch.pl	2011-06-27 20:02:28 +0000
@@ -34,6 +34,7 @@
             my($kernel, $hostname, $release, $version, $cpu) = POSIX::uname();
             if ($cpu =~ m/Power Macintosh/) { return "darwin-ppc";  }
             elsif ($cpu =~ m/i386/)         { return "darwin-x86";  }
+            elsif ($cpu =~ m/x86_64/)       { return "darwin-x86";  }
             else                            { return "unsupported"; }
     } else { return "unsupported"; }
 }