I spent about an hour compiling MySQL Workbench from source earlier today. After about 20 newly satisfied dependencies and an hour of actual building, I fired it up and discovered I wasn’t able to connect to any MySQL server through an SSH tunnel, which I have to be able to do.
I was able to find a deb package, mysql-workbench-gpl-5.2.39-1ubu1004-i386.deb, that seems to work quite well on Debian Squeeze 6.0.6. The package was mentioned in this forum post at debian.net. The package itself was the MySQL-provided deb for Ubuntu 10.04.
After I installed that deb, MySQL Workbench was able to connect to a MySQL server through an SSH tunnel. I must, must remember this for future Debian Squeeze installs.