Hi,

> Special characters like german umlauts (äöü, etc.) are replaced with
> the character '?' under Linux.
>
> This a a tomcat 4.1.24 based web-application. When I run my App on
> Tomcat/Windows against the same firebird Linux-instance there's no
> problem. So I blame the driver and imagine the driver needs something
> on the system to be able to return these characters? The database,
> table and column have character set "NONE".

What's the language setting on your Linux box? I suspect it is "C". If
you have database with "NONE" encoding then the only possibile way to
solve your problem is to set system language to German. Also you can
start your JVM with -Dfile.encoding=Cp1252 parameter, but this might
not work on some JVMs.

> I also tried to set the character set via "?lc_ctype=UNICODE_FSS"
> but received an unrecognized transaction error.

This will not work with "NONE" database, however exception should be
"Cannot transliterate character between character sets". If this is
not the case, I would be greatful, if you can post error message here.

Best regards,
Roman Rokytskyy