OSX Mountain Lion: CommandInvokationError: Failed to build apk.

I was building APKs just fine on an earlier OSX, but after a clean fresh install of Mountain Lion, I'm unable to build an APK for one particular project. Of course it's the project I've been putting a lot of time on lately.

The error message is odd, like something is mis-configured.

Error: Not a file '/Users/halley/cc/halley/unity/import-project'

Error: Not a file '/Users/halley/cc/halley/unity/import-project'

Error building Player: CommandInvokationFailure: Failed to build apk. See the Console for details. /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home/bin/java -Xmx1024M -Dcom.android.sdkmanager.toolsdir="/Users/halley/bin/android/sdk/tools" -Dfile.encoding=UTF8 -jar "/Applications/Unity/Unity.app/Contents/BuildTargetTools/AndroidPlayer/sdktools.jar" -

stderr[ Error: Not a file '/Users/halley/cc/halley/unity/import-project' ] stdout[

]

Yes, the given path is not a file. It's a directory. It's the directory that the project is in. I'm not sure what file it's trying to read or write when the message pops up.

I was able to make an APK from another project, and have verified I am using the right keystore/passwords to finish the APK. I'm not using any extra jars or plugins, and this problem exists with ADK r21. Since I can build another project, I don't think it's due to any special Java compiler version problem.

Any other ideas?