I tested java/net/InetAddress/CheckJNI from regression suite. And it hanged on RHEL5_64, it hanged with strings on out: ----------System.out:(4/109)----------
Testing IPv4 Socket/ServerSocket
Testing IPv4 DatagramSocket
Testing IPv6 Socket
Testing IPv6 DatagramSocket It happens on code: static void testDatagrams (DatagramSocket s1, DatagramSocket s2) throws Exception {
DatagramPacket p1 = new DatagramPacket (
"hello world".getBytes(),
0, "hello world".length(), s2.getLocalAddress(),
s2.getLocalPort()
);

DatagramPacket p2 = new DatagramPacket (new byte[128], 128);
s1.send (p1);// After this it hanged
s2.receive (p2);
It sends bytes, but do not receive it, and it wait for it, so it has error(timed out)