There is actually an issue for this: http://issues.gradle.org/browse/GRADLE-1715
I’m having a similar problem with the bnd library. The version bundled with Gradle is 1.50 and we’re running the latest release 2.1. Everything works at build-time, but havings tests in buildSrc fails miserably.
Is there any workaround available you know of? Is there a way to turn off the tests in buildSrc?