Hello, your original snippet works just fine for me with milestone-7. are you sure you haven’t any typos there? To provide the Exec task with input during your key tool is executed, you can redirect the standard input/output using the standardInput and standardOutput property of Exec. The DSL reference of Exec has the details: http://gradle.org/docs/current/dsl/org.gradle.api.tasks.Exec.html
I have just tried again with the same result. Then put the task alone in a file, it worked. Then checked the whole build script and recognized a change my IDE made unnoticed: it imported an ant Exec tag.
I missed that part of the DSL, thanks for calling my attention to it.