I just downloaded the current 5.5.16 and it is the exact same number of bytes as the one that gave me problems so I'd guess that it hasn't been rolled back.
According to the response I got on the Tomcat mailing list the bug will be fixed in 5.5.17.
'Re: 5.5.15 and JDK 1.4.2_08 to 5.5.16 andJDK 1.5.0_06 yields an extra' - MARC
Greetings.
Marcus