K Kuma [08-04-09 12.54] :

> (1) Firebird
> FirebirdSS-2.1.0.17755-ReleaseCandidate2.amd64.rpm
> (2) CentOS
> CentOS 5.1 X86_64
> (3) Installation steps
> a. install compat-libstdc++-33-3.2.3-61.i386.rpm
> this rpm is in CentOS installation disc #3.

you choosed Firebird x86_64, you need compat-lib x86_64, not i386
get compat-libstdc++-33-3.2.3-61.x86_64.rpm

http://rpm.pbone.net/index.php3/stat/4/idpl/5533044/com/compat-libstdc++-33-3.2.3-61.x86_64.rpm.html