See the attached thread dump. The interesting part is:

    Finalize me queue lock: unowned
        Waiting to be notified:
            "AWT-Motif"
and
         sun.awt.motif.MToolkit@ED9ABE68/EDAB2BB0 (key=0xed9abe68): monitor owner ecee1de0: "AWT-Motif"
        Waiting to enter:
            "Finalizer thread"
        Waiting to be notified:
            "AWT-Input"

the AWT-Motif thread is doing this:
    "AWT-Motif" (TID:0xed9abef0, sys_thread_t:0xecee1de0, state:CW) prio=5
        java.lang.Thread.run(Thread.java)
and the Finalizer thread is trying to finalize a graphics:
    "Finalizer thread" (TID:0xed9982b0, sys_thread_t:0xed271de0, state:MW) prio=1
        java.awt.Graphics.finalize(Graphics.java)


The scenario that produced this is uninteresting, because it's (of course)
thoroughly unreproducable. Basically I was running HotJava (it happened
to hang when I cloned a window and pressed reload).