AFAIR, upcoming Firebird 3.0 will be unable to read databases with ODS
< 12, unless it comes with a provider allowing this.

Carlos
Firebird Performance in Detail - http://videos.firebirddevelopersday.com
www.firebirdnews.org - www.FireBase.com.br

h> Is it safe to assume that new versions of Firebird will be
h> compatible with earlier databases? For example, will a DB created
h> in 2.1 work when opened by a 2.5 engine? I am assuming there is no
h> guarantee, but I didn't know if there was an attempt at backward compatibility.