upon deployment in production, I get this error , I don't understand where is coming from this 5.5.30... but I uninstalled the gem locally (oSX) and remotely (Debian) and reinstalled it... so it should be compiled with the latest libraries.. 5.6.19
here are both MySQL versions installed ...
on Debian
         mysql -u root -p -e 'SHOW VARIABLES LIKE "%version%";'
        Enter password: 
        +-------------------------+-------------------+
        | Variable_name           | Value             |
        +-------------------------+-------------------+
        | innodb_version          | 5.6.19            |
        | protocol_version        | 10                |
        | slave_type_conversions  |                   |
        | version                 | 5.6.19-1~dotdeb.1 |
        | version_comment         | (Debian)          |
        | version_compile_machine | x86_64            |
        | version_compile_os      | debian-linux-gnu  |
        +-------------------------+-------------------+
on OSX
        yves$ mysql -u root -p -e 'SHOW VARIABLES LIKE "%version%";'
        Enter password: 
        +-------------------------+------------------------------+
        | Variable_name           | Value                        |
        +-------------------------+------------------------------+
        | innodb_version          | 5.6.19                       |
        | protocol_version        | 10                           |
        | slave_type_conversions  |                              |
        | version                 | 5.6.19                       |
        | version_comment         | MySQL Community Server (GPL) |
        | version_compile_machine | x86_64                       |
        | version_compile_os      | osx10.7                      |
        +-------------------------+------------------------------+