ESB: groovy_gateway quickstart causes server stack trace

When the groovy_gateway quickstart deploys, it tries to run a gui console to feed message to a service, but the server logs:
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16:59:51,420 INFO [EsbDeployment] Starting ESB Deployment 'Quickstart_groovy_gateway.esb'
16:59:52,282 INFO [GroovyGateway] Starting Groovy Gateway listener
16:59:53,347 WARN [AbstractThreadedManagedLifecycle] Unexpected error from doRun()
java.lang.RuntimeException: Failed to create component for 'frame' reason: java.awt.HeadlessException
at groovy.util.FactoryBuilderSupport.createNode(FactoryBuilderSupport.java:354)
at groovy.util.FactoryBuilderSupport.doInvokeMethod(FactoryBuilderSupport.java:405)
at groovy.util.FactoryBuilderSupport.invokeMethod(FactoryBuilderSupport.java:207)
at org.codehaus.groovy.runtime.InvokerHelper.invokePogoMethod(InvokerHelper.java:781)
at org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:757)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeMethodN(ScriptBytecodeAdapter.java:167)
at Script1.run(Script1.groovy:37)
at org.jboss.soa.esb.listeners.gateway.GroovyGateway.doRun(GroovyGateway.java:143)
at org.jboss.soa.esb.listeners.lifecycle.AbstractThreadedManagedLifecycle.run(AbstractThreadedManagedLifecycle.java:115)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.awt.HeadlessException
at java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:159)
at java.awt.Window.<init>(Window.java:432)
at java.awt.Frame.<init>(Frame.java:403)
at java.awt.Frame.<init>(Frame.java:368)
at javax.swing.JFrame.<init>(JFrame.java:158)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at org.codehaus.groovy.runtime.MetaClassHelper.doConstructorInvoke(MetaClassHelper.java:528)
at groovy.lang.MetaClassImpl.doConstructorInvoke(MetaClassImpl.java:2347)
at groovy.lang.MetaClassImpl.invokeConstructor(MetaClassImpl.java:1244)
at groovy.lang.MetaClassImpl.invokeConstructor(MetaClassImpl.java:1174)
at org.codehaus.groovy.runtime.InvokerHelper.invokeConstructorOf(InvokerHelper.java:805)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeNewN(ScriptBytecodeAdapter.java:227)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.invokeNew0(ScriptBytecodeAdapter.java:234)
at groovy.swing.factory.FrameFactory.newInstance(FrameFactory.groovy:29)
at groovy.util.FactoryBuilderSupport.createNode(FactoryBuilderSupport.java:344)
... 9 more