How to use getStartupArgs()

Since 0.9.1 it seems you can read the command line arguments issue #245 with the getStartupArgs() method (documentation)

But I do know how to use it, I've put it in in all the Griffon lifecycle, Controller, Service, and I get the exception

org.codehaus.groovy.runtime.InvokerInvocationException: groovy.lang.MissingMethodException: No signature of method: [LifeCycle|Controller|Service].getStartupArgs() is applicable for argument types: () values: []
Caused by: groovy.lang.MissingMethodException: No signature of method: [LifeCycle|Controller|Service].getStartupArgs() is applicable for argument types: () values: [

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