I get this JVM crash at each time on Windows.
Tried Java 6 U14 and U26.
The context is a test loading plenty of fxml files, one after the other, doing a renderingToImage and comparison against reference.
Before the crash I get several exceptions as described in the RT-14955 (NPE); I dunno if the JVM comes to a state the next NPE kills it or if root cause is completely separated from what is described in RT-14955.
What is sure however is that the crash occurs only if you run the test on the whole set of fxml files: if you run it only against the fxml file which is processed at crash time then it goes perfectly well.

     [java] # EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x72720c9a, pid=3552, tid=2884
     [java] #
     [java] # JRE version: 6.0_26-b03
     [java] # Java VM: Java HotSpot(TM) Client VM (20.1-b02 mixed mode windows-x86 )
     [java] # Problematic frame:
     [java] # C [javafx-font.dll+0x30c9a]