Starting from jdk6.0-b27 javac generates different source code
position in
CharacterRangeTable attribute (under -Xjcov mode).
Originally a source position in the CRT was packed as
(linenumber<<10)|position_in_line.Starting from b27 it seems
represented as a position from a beginning of source file.

A problem is that the change breaks JCov utilities and JDK SQE
cannot generate
coverage reports because of this.