When javadoc runs, it includes a comment near the top of each generated file that looks like

<!-- Generated by javadoc (build 1.6.0_05) on Tue Jul 15 16:42:08 PDT 2008 -->

The problem is that because of the way that javadoc is run when creating the JDK API docs, the build info (1.6.0_05 in this case) is the info for the bootstrap JDK, and not the version of javadoc actually in use.

This is a side effect of the way javadoc is run, using the following, in jdk/make/common/shared/Defs-java.gmk

  JAVADOC_CMD = $(BOOT_JAVA_CMD) \
                "-Xbootclasspath/p:$(JAVADOC_JAR)$(CLASSPATH_SEPARATOR)$(JAVAC_JAR)$(CLASSPATH_SEPARATOR)$(DOCLETS_JAR)" \
                -jar $(JAVADOC_JAR)