Java SE 6 Update 20 Release Notes. - Oracle | Hardware and Software, Engineered to Work Together

Changes in 1.6.0_20 (6u20) The full internal version number for this update release is 1.6.0_20-b02 (where "b" means "build"). The external version number is 6u20. OlsonData 2010b 6u20 contains Olson time zone data version 2010b. For more information, ref

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