According to the API spec of ImageWriter.endWriteSequence(), this method is supposed to throw an IllegalStateException when prepareWriteSequence() is not called prior to this. I am just creating a writer and calling this method directly. This method does not throw an IllegalStateException.

This is reproducible on all platforms with the following PIT build:
java version "1.6.0-2d.pit-jcg-win-03"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.6.0-2d.pit-jcg-win-03-java2d_23_may_2005_02_25-b00)
Java HotSpot(TM) Client VM (build 1.6.0-ea-b37, mixed mode)

I have attached a sample test. Execute the sample test. If you dont see any IllegalStateException on the console, the bug is reproduced.
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