I have just remembered this...
Current libgda contains a bug when connecting to MySQL v4 databases.
Problem (copy my original post on gnome-db list):

I an just trying to use gda-browser to connect to a mysql server, and
I just get an error on startup about the syntax of 'where Variable_name = ...'
thing. I will reproduce it from  mysql (well, really mariadb) cli client:

werewolf:~> mysql --host=xxxxx --user=magallon --password=xxxxx magallon
Welcome to the MariaDB monitor.  Commands end with ; or \g.
...
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MySQL [magallon]> show variables where Variable_name='lower_case_table_names';
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'where Variable_name='lower_case_table_names'' at line 1

This is the error I get from gda-browser-5.0 on connection.

It looks like the sorrect syntax is something like:

MySQL [magallon]> show variables like 'lower_case_table_names';
+------------------------+-------+
| Variable_name          | Value |
+------------------------+-------+
| lower_case_table_names | 0     |
+------------------------+-------+
1 row in set (0.06 sec)

Is this really a bug ? Is mysql 4.1 too old for gda ?

Response is here:

http://mail.gnome.org/archives/gnome-db-list/2012-January/msg00019.html

And patch here:

http://git.gnome.org/browse/libgda/commit/?id=96398ab6e71b5a966f34d8729d8c1213e9189c16

Probably this can go in even in freeze, as it is a bug fix, but maintainers decide.