Internal Error: IllegalAccessError (OSX)

When invoking Gradle I get

java.lang.IllegalAccessError: tried to access class org.jruby.ext.posix.BaseNativePOSIX from class org.gradle.internal.nativeplatform.filesystem.FileSystemServices

Gradle 1.7 and 1.6 OSX 10.7.5 Java version 1.7 (and tested with 1.6 – even tried -d32)

Full stack trace:

I even tried to build Gradle myself, but get the same problem when building Gradle itself

Found an old jruby under


that was in the way

(found it by using

After removing it, Gradle worked fine.