Problem with Grass

Hello,
https://code.google.com/p/l2jserver-client/source/browse/trunk/Netbeans/GrassLayer/
I’m using Grass Layer plugin from repository. This plugin allows to add Spatial - Grass… inside Scene Composer, but when I try to set up my grass, it returns me only error:

org.netbeans.ExitSecurityException: Illegal attempt to exit early
    at org.netbeans.TopSecurityManager.checkExitImpl(TopSecurityManager.java:218)
    at org.netbeans.TopSecurityManager$PrivilegedCheck.run(TopSecurityManager.java:781)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.netbeans.TopSecurityManager$PrivilegedCheck.check(TopSecurityManager.java:806)
    at org.netbeans.TopSecurityManager$PrivilegedCheck.checkExit(TopSecurityManager.java:794)
    at org.netbeans.TopSecurityManager.checkExit(TopSecurityManager.java:158)
    at java.lang.Runtime.exit(Runtime.java:107)
    at java.lang.System.exit(System.java:962)
    at com.l2client.util.GrassLayerUtil.createPatchField(GrassLayerUtil.java:121)
    at com.l2client.grassmodule.AddGrassLayerWizardAction.generateGrass(AddGrassLayerWizardAction.java:85)
    at com.l2client.grassmodule.AddGrassLayerWizardAction.doCreateSpatial(AddGrassLayerWizardAction.java:68)
    at com.jme3.gde.core.sceneexplorer.nodes.actions.AbstractNewSpatialWizardAction$1$1.call(AbstractNewSpatialWizardAction.java:73)
    at com.jme3.gde.core.sceneexplorer.nodes.actions.AbstractNewSpatialWizardAction$1$1.call(AbstractNewSpatialWizardAction.java:70)
    at com.jme3.app.AppTask.invoke(AppTask.java:142)
    at com.jme3.app.Application.runQueuedTasks(Application.java:583)
    at com.jme3.app.Application.update(Application.java:596)
    at com.jme3.gde.core.scene.SceneApplication.update(SceneApplication.java:302)
    at com.jme3.system.lwjgl.LwjglAbstractDisplay.runLoop(LwjglAbstractDisplay.java:151)
    at com.jme3.system.lwjgl.LwjglCanvas.runLoop(LwjglCanvas.java:229)
    at com.jme3.system.lwjgl.LwjglAbstractDisplay.run(LwjglAbstractDisplay.java:228)
    at java.lang.Thread.run(Thread.java:744)

Looks like the “GrassLayerUtil” calls System.exit…