We are seeing the same thing that Samuel Wolf described, but from our web
UI and with 7.0.28-4+deb7u10. We get seemingly random 400 HTTP returns.
We downgraded to 7.0.28-4+deb7u4 and that problem went away.
Unfortunately in our environment the Tomcat-side Java exception is not
being logged, so we have some more digging to do. We do see the 400 error
in the access log though.
This is the maintainer address of Debian's Java team
debian-j...@lists.debian.org for discussions and questions.