Dotdeb.org has released MySQL 5.1.56 packages for Debian GNU/Linux
MySQL 5.1.56 packages are now available on Dotdeb :MySQL 5.1.56 for Debian available
for Debian 6.0 "Squeeze" and Debian 5.0 "Lenny"
for the amd64 and i386 architectures
Of course, the corresponding Pinba storage engine has been rebuilt (Squeeze only).