> Please hint how to set -DFBLog4j=true in tomcat startup script. I
> edited /etc/init.d/tomcat, wrote there two new lines

> JAVA_OPTS="-DFBLog4j=true"
> export JAVA_OPTS

> tried without "-D" either...

In Tomcat 5.5 your approach should work (the -D must be there), cannot tell
about other versions. Change the line that starts Java - prepend "echo " to
it and check what is really started.

However, "No appenders..." usually means that log4j could not find
acceptable configuration. Check what log4j.properties or log4j.xml are used
in fact. That will be those that are first in the classpath.

> how can it notice db server version change, i wonder...

For example, if you try to pass isc_dpb_num_buffers=75 to SS it will not
accept connections, though for CS it will work ok. SS and CS are almost the
same, but not really the same. I do not say that it is what happens, but
that can be a reason. And if it is, we should find the reason either in
JayBird or in Firebird and fix it - that is not intended behaviour.

Roman