"jar uf" changes file permissions unexpectedly

There seems a regression in jdk6u33 (linux am64)
Jar command changes the permission of file.

REPRODUCE :
1. run "umask 022"
2. run "jar cvf new-file any-file"
3. confirm the permission of new-file in the above step2
  (permission is set to 644)
4. run "jar uvf new-file any-file2"
5. confirm the permission of new-file again.
You can see the permission is changed to 600

FREQUENCY:
This problem occurs every time the command is run.

EXPECTED:
The behavior in jdk6u32 is expected.(permission is not changed by jar command)
---- JDK6u32 ---
jle-esxi-redhat:/home/tbaba 42 % umask 022
jle-esxi-redhat:/home/tbaba 43 % jar cvf test.jar te.csh
added manifest
adding: te.csh(in = 476) (out= 96)(deflated 79%)
jle-esxi-redhat:/home/tbaba 44 % ls -l test.jar
-rw-r--r--+ 1 tbaba javasoft 545 Jun 10 23:25 test.jar
jle-esxi-redhat:/home/tbaba 45 % jar uvf test.jar cmd
adding: cmd(in = 149) (out= 91)(deflated 38%)
jle-esxi-redhat:/home/tbaba 46 % ls -l test.jar
-rw-r--r--+ 1 tbaba javasoft 734 Jun 10 23:25 test.jar
jle-esxi-redhat:/home/tbaba 47 % java -version
java version "1.6.0_32"
Java(TM) SE Runtime Environment (build 1.6.0_32-b05)
Java HotSpot(TM) 64-Bit Server VM (build 20.7-b02, mixed mode)
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ACTUAL:
Permission of file is changed by jar command.
--- JDK6u33 ----
jle-esxi-redhat:/home/tbaba 43 % umask 022
jle-esxi-redhat:/home/tbaba 44 % jar cvf test.jar te.csh
added manifest
adding: te.csh(in = 476) (out= 96)(deflated 79%)
jle-esxi-redhat:/home/tbaba 45 % ls -l test.jar
-rw-r--r--+ 1 tbaba javasoft 545 Jun 10 23:28 test.jar
jle-esxi-redhat:/home/tbaba 46 % jar uvf test.jar cmd
adding: cmd(in = 149) (out= 91)(deflated 38%)
jle-esxi-redhat:/home/tbaba 47 % ls -l test.jar
-rw-------+ 1 tbaba javasoft 734 Jun 10 23:29 test.jar <==== Permission is changed !!
jle-esxi-redhat:/home/tbaba 48 % java -version
java version "1.6.0_33"
Java(TM) SE Runtime Environment (build 1.6.0_33-b03)
Java HotSpot(TM) 64-Bit Server VM (build 20.8-b03, mixed mode)
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