R help - Apr 2011 - RODBC with MySQL sees tables, but queries return zero rows

Hi All,
I'm using RODBC to tap into MySQL on a remote server.  It appears like
the connection is successful:  I can see all tables and columns in my
database.  However, queries return zero lines, including queries I've
verified as functional and non-empty by entering them directly in
MySQL.

I granted myself all privileges to the database, as per
http://www.actualtech.com/mysql_remote.php, by entering this into
mysql:
GRANT ALL ON your_database_name.* TO your_user_id@'%' IDENTIFIED BY
'your_password';

I've opened ports on my server, as per
http://forums.systeminetwork.com/isnetforums/showthread.php?t=42086

My setup:
mysql  Ver 14.12 Distrib 5.0.77, for redhat-linux-gnu (x86_64) using
readline 5.1
R 2.10.0 GUI 1.30 Leopard build 32-bit (5511)
Mac OS X 10.6.7
MySQL/PostgreSQL/SQLite driver purchased from
http://www.actualtechnologies.com/products.php, as per the RODBC
documentation

Any tips?
Thanks in advance,
Dan