Packages of MySQL 5.5.30 are now available for Debian 6.0 “Squeeze” on both amd64 and i386 architectures. They fixes some InnoDB-, partition- and replication-related issues and some more bugs. And a new configuration directive, called innodb_print_all_deadlocks, has been backported from MySQL 5.6.
Please note that the Pinba engine has also been rebuilt to be used against this new version.
As usual, please read carefully the full Changelog before upgrading.