Alright, after some research it looks like it does work on the Mac, but you need to update your version of Java. The forum poster said to go here: support.apple.com/downloads/
and search for Java 1.6. Once you've downloaded and installed Java 1.6, go to Applications/Utilities/Java Preferences, and on the "General" tab drag the Java 1.6 option to the top of the list to make sure that your computer tries to run Java programs with version 1.6.
Then download the WebOS doctor here and "carefully follow instructions".
Let me know if this works. If it doesn't, reply to this answer and I'll keep searching.
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