This behavior is related to an intentional change in Java6SR16FP20 to tighten security by disabling the MD5 algorithm by default in latest JVM release. The Domino Server Controller, however, currently requires MD5. IBM is investigating a solution to leverage a more secure cipher for the Domino Server Controller (a.k.a. Domino Java Console). This issue is tracked as SPR# RSSNA6UU79.
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