MySQL includes a connection option MYSQL_ENABLE_CLEARTEXT_PLUGIN since 5.5.27. The problem is that some other projects does quite dummy check at a time they want to use it, like mysql-connector-odbc-5.2.5-src/driver/connect.c:259 does:

#if (MYSQL_VERSION_ID >= 50527 && MYSQL_VERSION_ID < 50600) || MYSQL_VERSION_ID >= 50607

MariaDB-5.5.31 doesn't include such connection option in its header file, which makes it incompatible from the mysql-connector-odbc-5.2.5 POV – the connector basically does not compile with mariadb-5.5.x.

If there is a reason why mariadb doesn't include MYSQL_ENABLE_CLEARTEXT_PLUGIN, it should be at least properly documented in the header file.