Fails on first run. Run it again, no problem

run:
     [java] Feb 20, 2013 1:28:18 PM demo.Main gotoLogin
     [java] SEVERE: null
     [java] java.lang.NullPointerException
     [java] at com.sun.javafx.fxml.BeanAdapter.coerce(BeanAdapter.java:384)
     [java] at javafx.fxml.FXMLLoader$Element.populateListFromString(FXMLLoader.java:484)
     [java] at javafx.fxml.FXMLLoader$Element.processValue(FXMLLoader.java:346)
     [java] at javafx.fxml.FXMLLoader$Element.processPropertyAttribute(FXMLLoader.java:317)
     [java] at javafx.fxml.FXMLLoader$Element.processInstancePropertyAttributes(FXMLLoader.java:229)
     [java] at javafx.fxml.FXMLLoader$ValueElement.processEndElement(FXMLLoader.java:633)
     [java] at javafx.fxml.FXMLLoader.processEndElement(FXMLLoader.java:2502)
     [java] at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2202)
     [java] at demo.Main.replaceSceneContent(Main.java:94)
     [java] at demo.Main.gotoLogin(Main.java:80)
     [java] at demo.Main.start(Main.java:43)
     [java] at com.sun.javafx.application.LauncherImpl$5.run(LauncherImpl.java:491)
     [java] at com.sun.javafx.application.PlatformImpl$6.run(PlatformImpl.java:260)
     [java] at com.sun.javafx.application.PlatformImpl$5$1.run(PlatformImpl.java:223)
     [java] at com.sun.javafx.application.PlatformImpl$5$1.run(PlatformImpl.java:220)
     [java] at java.security.AccessController.doPrivileged(Native Method)
     [java] at com.sun.javafx.application.PlatformImpl$5.run(PlatformImpl.java:220)
     [java] at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
     [java]