IncompatibleClassChangeError when using closures

99 /tmp> ~/Downloads/groovy-2.1.2/bin/groovy q
Here's the problem?!?
-- nope was actually OK
100 /tmp> ~/Downloads/groovy-2.2.1/bin/groovy q
Here's the problem?!?
-- nope was actually OK
101 /tmp> ~/Downloads/groovy-2.3.1/bin/groovy q
Here's the problem?!?
Caught: java.lang.IncompatibleClassChangeError
java.lang.IncompatibleClassChangeError
        at Foo$_bar_closure1.doCall(q.groovy:10)
        at Foo$_bar_closure1.doCall(q.groovy)
        at Foo.justcallme(q.groovy:3)
        at Foo$justcallme$0.callStatic(Unknown Source)
        at Foo.bar(q.groovy:8)
        at Foo$bar.call(Unknown Source)
        at q.run(q.groovy:15)
102 /tmp> <q.groovy
class Foo {
    static justcallme(Closure block) {
        block()
    }
    static foo() {
    }
    static void bar(Closure block) {
        this.justcallme {
println "Here's the problem?!?"
            this.foo()
println "-- nope was actually OK"
        }
    }
}
Foo.bar() { }
103 /tmp> groovy -v
Groovy Version: 2.3.1 JVM: 1.7.0_13 Vendor: Oracle Corporation OS: Mac OS X
104 /tmp> sw_vers
ProductName:    Mac OS X
ProductVersion: 10.8.5
BuildVersion:   12F45
105 /tmp>