test java/net/PortUnreachableException/OneExceptionOnly.java failed on longhorn, tested with jdk7_b24 and nightly, see the output as below:

***
Test Description:
    - Send 10 datagrams to bad destination
    - <wait a wee while>
    - Send another datagram - should throw PUE or timeout
    - Receive another receive - a SocketTimeoutException expected

Expected PUE not thrown - packets probably discarded (Passed).

***
Test Description:
    - Send 10 datagrams to bad destination
    - <wait a wee while>
    - Receive another datagram - should throw PUE or timeout
    - Receive another receive - a SocketTimeoutException expected

Expected PortUnreachableException thrown - good!
Exception in thread "main" java.lang.Exception: Unexpected PUE received - assume
d that PUs would be consumed
        at OneExceptionOnly.doTest(OneExceptionOnly.java:113)
        at OneExceptionOnly.main(OneExceptionOnly.java:140)