Try to run a manual regression test closed/java/awt/event/MouseEvent/MouseEventsDuringDrag on XToolkit with jdk8 (circa b38). Chance is, you will get
 
java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData
at sun.java2d.xr.XRRenderer.validateSurface(XRRenderer.java:65)
at sun.java2d.xr.XRRenderer.drawLine(XRRenderer.java:84)
at sun.java2d.SunGraphics2D.drawLine(SunGraphics2D.java:2137)
at sun.awt.X11.XTextAreaPeer$BevelBorder.paintBorder(XTextAreaPeer.java:1233)
at javax.swing.border.CompoundBorder.paintBorder(CompoundBorder.java:117)
at javax.swing.JComponent.paintBorder(JComponent.java:947)
at javax.swing.JComponent.paint(JComponent.java:1055)
at javax.swing.JComponent.paintToOffscreen(JComponent.java:5224)
at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1486)
at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1417)
at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:306)
at javax.swing.RepaintManager.paint(RepaintManager.java:1210)
at javax.swing.JComponent._paintImmediately(JComponent.java:5172)
at javax.swing.JComponent.paintImmediately(JComponent.java:4983)
at javax.swing.JComponent.paintImmediately(JComponent.java:4995)
at sun.awt.X11.XTextAreaPeer$AWTTextArea.repaintNow(XTextAreaPeer.java:994)
at sun.awt.X11.XTextAreaPeer.repaintText(XTextAreaPeer.java:283)
at sun.awt.X11.XTextAreaPeer.setText(XTextAreaPeer.java:461)
at java.awt.TextComponent.setText(TextComponent.java:239)
at TestDialog.printInstructions(MouseEventsDuringDrag.java:266)
at Sysout.createDialogWithInstructions(MouseEventsDuringDrag.java:203)
at MouseEventsDuringDrag.init(MouseEventsDuringDrag.java:107)
at com.sun.javatest.regtest.AppletWrapper$AppletRunnable.run(AppletWrapper.java:150)
at java.lang.Thread.run(Thread.java:722)


Linux Ubuntu 11.10 x586
(Ubuntu) version of libxrender1 is 1:0.9.6-2 while the last note from Changelog is: "Bump Standards-Version to 3.9.2."