JBDS Installer: Exception when version is selected in combo box

Exception occurs when I'm trying to select version in combo

at net.sourceforge.mlf.metouia.MetouiaScrollPaneUI.paint(MetouiaScrollPaneUI.java:89)
at javax.swing.plaf.ComponentUI.update(ComponentUI.java:142)
at javax.swing.JComponent.paintComponent(JComponent.java:743)
at javax.swing.JComponent.paint(JComponent.java:1006)
at javax.swing.JComponent.paintChildren(JComponent.java:843)

it seems problem in installed L&F in line below
Rectangle vbounds = scrollpane.getHorizontalScrollBar().getBounds();
because scrollpane.getHorizontalScrollBar() returns null.