I suspect that the FTBFS is related to the upgrade of to
libhamcrest-java to 1.2 (see
jmock2 builds on squeeze with libhamcrest-java (1.1) installed. Ubuntu
precise also uses libhamcrest-java (1.1) to build jmock2.
This is the maintainer address of Debian's Java team
debian-j...@lists.debian.org for discussions and questions.