MySQL grant syntax and use of wildcards??

[unixNAB]

MySQL 5.0.x

Hello,
I'm trying to work out but the MySQL reference guide to the grant syntax is a little off, it says...

Note
the ‘_’ and ‘%’ wildcards are allowed when specifying database names in GRANT statements that grant privileges at the global or database levels. This means, for example, that if you want to use a ‘_’ character as part of a database name, you should specify it as ‘\_’ in the GRANT statement, to prevent the user from being able to access additional databases matching the wildcard pattern; for example, GRANT ... ON `foo\_bar`.* TO ....

so i wanted to do something like

grant all on %_log.* to .......;
and also tried
grant all on %\_log.* to ......;

Neither worked now what i'm tring to do is allow a user access to any database that has anything in the name before the "_log" part, basically if in unix or linux a *_log type thing. Is this possible so i dont have to ever keep on adding or changing grants the user has to each database named <whatever>_log or is the only way to constantly have to change and use the real database name???

Thanks and regards
Mark