JISAutoDetect outputs bufferOverFlowException in 1.5-beta2-b51

JISAutoDetect outputs bufferOverFlowException in 1.5b51.
The attached program works well in 1.4.2_03.

REPRODUCE;
 1) Compile the attached program(StringTest.java).
 2) Launch "java -showversion StringTest
 
d:\temp>java -showversion StringTest
java version "1.5.0-beta2"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0-beta2-b51)
Java HotSpot(TM) Client VM (build 1.5.0-beta2-b51, mixed mode)
Locale=ja_JP
java.nio.BufferOverflowException
        at java.nio.charset.CoderResult.throwException(CoderResult.java:259)
        at java.lang.StringCoding$CharsetSD.decode(StringCoding.java:186)
        at java.lang.StringCoding.decode(StringCoding.java:222)
        at java.lang.String.<init>(String.java:412)
        at java.lang.String.<init>(String.java:440)
        at StringTest.run(StringTest.java:16)
        at StringTest.main(StringTest.java:10)

CONFIGURATION:
   OS : WindowsXP (Sp1, japanese)
   JRE: 1.5 beta2 b51
   
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