Problem:
When trying to connect to database after setting the character set, 
WISQL or ISQL returns error "character set xxx not defined".  


Solution:
Check if the following scenerio matches your problem:


* You have a database with a character set.  Something like this:

sql>create database "c:tempinternational.gdb" default character set 
win1252;


* In another  isql session, attempt to connect to the database.

sql>set names win1252;
sql>connect "c:tempinternational.gdb";

* It will error out with this:

"bad parameters on attach or create database
-CHARACTER SET WIN1252 is not defined"

*  And you are using InterBase version WI-V5.1.1.680.

If your problem matches the above case, this is due to a bug on IB version WI-V5.1.1.680.
This problem is fixed in version WI-V5.5.737.