stylesheet css with number arguments fails with a conversion exception

the following exception is thrown when using a "number" argument in a stylesheet. Attached sample is based on the customcontrol sample in baloo. attached sample project for ease of duplication.
compile:
jar:
standard-run:
java.lang.ClassCastException: java.lang.Double
        at com.sun.javafx.runtime.location.FloatVariable.set(FloatVariable.java:38)
        at javafx.reflect.FXLocal$VarMember.setValue(FXLocal.java:729)
        at com.sun.stylesheet.javafx.Attribute.setProperty(Attribute.java:153)
        at com.sun.stylesheet.javafx.FXObjectStyleSupport.setProperty(FXObjectStyleSupport.java:342)
        at com.sun.stylesheet.styleable.DefaultStyleable.setProperty(DefaultStyleable.java:168)
        at com.sun.stylesheet.PropertyManager.applyProperty(PropertyManager.java:594)
        at com.sun.stylesheet.PropertyManager.applyProperty(PropertyManager.java:555)
        at com.sun.stylesheet.Declaration.applyTo(Declaration.java:91)
        at com.sun.stylesheet.Rule.applyTo(Rule.java:221)
        at com.sun.stylesheet.Stylesheet.applyTo(Stylesheet.java:277)
        at com.sun.stylesheet.Stylesheet.applyTo(Stylesheet.java:282)
        at com.sun.stylesheet.Stylesheet.applyTo(Stylesheet.java:257)
        at javafx.scene.Scene.applyStylesheets$impl(Scene.fx:235)
        at javafx.scene.Scene.applyStylesheets(Scene.fx:43)
        at javafx.scene.Scene.userInit$(Scene.fx:220)
        at javafx.scene.Scene.initialize$(Scene.fx:43)
        at customcontrol.Main.javafx$run$(Main.fx:21)
        at customcontrol.Main.javafx$run$(Main.fx:21)
browser-run: