Please look at http://docs.oracle.com/javafx/2/api/javafx/scene/control/Tab.html#isDisabled();
It says that when tab pane is disabled, method should return true, but it doesn't.

To reproduce:
1. Open app;
2. Push the button;
3. You will see that isDisabled() isn't 'true' for tabs in the disabled tab pane.

import java.util.Iterator;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Tab;
import javafx.scene.control.TabPane;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;

public class JavaFXApplication62 extends Application {

    @Override
    public void start(Stage stage) {

        final TabPane tp1 = new TabPane();
        tp1.getTabs().addAll(new Tab("11"), new Tab("12"));
        
        Tab disabledTab = new Tab("Disabled");
        disabledTab.setDisable(true);
        tp1.getTabs().add(disabledTab);
         
        tp1.setStyle("-fx-border-color:GREEN");
        tp1.setMinWidth(150);
        tp1.setPrefWidth(150);
        tp1.setMaxWidth(150);
        tp1.setMinHeight(150);
        tp1.setPrefHeight(150);
        tp1.setMaxHeight(150);

        final TabPane tp2 = new TabPane();
        tp2.getTabs().addAll(new Tab("21"), new Tab("22"));
        
        Tab secondDisaTab = new Tab("Disabled - 2");
        secondDisaTab.setDisable(true);
        
        tp2.getTabs().add(secondDisaTab);
        
        tp2.setStyle("-fx-border-color:GREEN");
        tp2.setMinWidth(150);
        tp2.setPrefWidth(150);
        tp2.setMaxWidth(150);
        tp2.setMinHeight(150);
        tp2.setPrefHeight(150);
        tp2.setMaxHeight(150);
        tp2.setDisable(true);
            
        HBox root = new HBox(20d);
        root.getChildren().addAll(tp1, tp2);

        Button btnShowProps = new Button("Show properties");
        btnShowProps.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent t) {
                for(Iterator<Tab> it : new Iterator [] {
                                        tp1.getTabs().iterator(),
                                        tp2.getTabs().iterator()})
                {
                    while(it.hasNext()) {
                        Tab tab = it.next();
                        System.out.println("Text = " + tab.getText());
                        System.out.println("isDisable() = " + tab.isDisable());
                        System.out.println("isDisabled() = " + tab.isDisabled());
                    }
                }
            }
        });

        root.getChildren().add(btnShowProps);

        Scene scene = new Scene(root, 400, 300);

        stage.setScene(scene);
        stage.setTitle(System.getProperty("java.runtime.version") + "; " + System.getProperty("javafx.runtime.version"));
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}