-A Mac OS X package that is compatible with
-versions 10.5 "Leopard" and later (including 10.6 "Snow Leopard") is
-available. The Mac operating system includes Java, and all Altus Metrum
-products show up as simple USB serial ports, so this should just work
-with no additional drivers or other dependency issues. Older versions of
-the Mac operating system come with Java versions that are too old for use
-with Altus Metrum software, and we know of no way to update the Java version
-other than upgrading to a newer operating system.
+A Mac OS X package that is compatible with versions 10.5 "Leopard" and
+later. The Mac operating system includes Java, and all Altus Metrum products
+show up as simple USB serial ports, so this should just work with no
+additional drivers or other dependency issues. Older versions of the Mac
+operating
+system, and even newer versions for PowerPC-based machines, come with
+Java version 5 or older, which is too old for use with Altus Metrum
+software. We know of no way to update the Java version other than
+upgrading to a newer operating system (for Intel based macs) or
+purchasing new hardware (for PowerPC based macs).
+
+If you have trouble installing on a Mac, and are getting errors about the
+package being corrupt, you may not be configured to allow installation of
+software from arbitrary sources. One customer running 10.8.1 reported that
+he was able to work around this by going to "System Preferences", "Security
+& Privacy", "General", and then clicking the "Anywhere" radio button where
+it askes "Allow applications downloaded from:".