org.apache.zookeeper.server.quorum.Zab1_0Test failed due to hard code with 33556 port

org.apache.zookeeper.server.quorum.Zab1_0Test was failed both with SUN JDK and open JDK.

[junit] Running org.apache.zookeeper.server.quorum.Zab1_0Test
[junit] Tests run: 8, Failures: 0, Errors: 1, Time elapsed: 18.334 sec
[junit] Test org.apache.zookeeper.server.quorum.Zab1_0Test FAILED

Zab1_0Test log:
Zab1_0Test log:
2012-07-11 23:17:15,579 [myid:] - INFO [main:Leader@427] - Shutdown called
java.lang.Exception: shutdown Leader! reason: end of test
at org.apache.zookeeper.server.quorum.Leader.shutdown(Leader.java:427)
at org.apache.zookeeper.server.quorum.Zab1_0Test.testLastAcceptedEpoch(Zab1_0Test.java:211)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:48)

2012-07-11 23:17:15,584 [myid:] - ERROR [main:Leader@139] - Couldn't bind to port 33556
java.net.BindException: Address already in use
at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:402)
at java.net.ServerSocket.bind(ServerSocket.java:328)
at java.net.ServerSocket.bind(ServerSocket.java:286)
at org.apache.zookeeper.server.quorum.Leader.<init>(Leader.java:137)
at org.apache.zookeeper.server.quorum.Zab1_0Test.createLeader(Zab1_0Test.java:810)
at org.apache.zookeeper.server.quorum.Zab1_0Test.testLeaderInElectingFollowers(Zab1_0Test.java:224)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

2012-07-11 23:17:20,202 [myid:] - ERROR [LearnerHandler-bdvm039.svl.ibm.com/9.30.122.48:40153:LearnerHandler@559] - Unex
pected exception causing shutdown while sock still open
java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
at java.io.BufferedInputStream.read(BufferedInputStream.java:237)
at java.io.DataInputStream.readInt(DataInputStream.java:370)
at org.apache.jute.BinaryInputArchive.readInt(BinaryInputArchive.java:63)
at org.apache.zookeeper.server.quorum.QuorumPacket.deserialize(QuorumPacket.java:83)
at org.apache.jute.BinaryInputArchive.readRecord(BinaryInputArchive.java:108)
at org.apache.zookeeper.server.quorum.LearnerHandler.run(LearnerHandler.java:291)
2012-07-11 23:17:20,203 [myid:] - WARN [LearnerHandler-bdvm039.svl.ibm.com/9.30.122.48:40153:LearnerHandler@569] - ****

• • • GOODBYE bdvm039.svl.ibm.com/9.30.122.48:40153 ********
      2012-07-11 23:17:20,204 [myid:] - INFO [Thread-20:Leader@421] - Shutting down
      2012-07-11 23:17:20,204 [myid:] - INFO [Thread-20:Leader@427] - Shutdown called
      java.lang.Exception: shutdown Leader! reason: lead ended

this failure seems 33556 port is already used, but it is not in use with command check in fact. There is a hard code in unit test, we can improve it with code patch.