Firebird was almost interesting...

Quote from planet.debian.org blog
"I was looking at the Firebird database recently. Free Software, very feature complete, and one neat feature was that it could run either client/server (like PostgreSQL) or as a standalone .so (like Sqlite). I was starting to look into using it.

Then I discovered it only supports i386 on Linux, and no progress has been made in 3 years on that."
False firebird is supported on other arhitectures

Firebird2 now builds and runs just fine on amd64.
Anyone with access to anything other than i386 or amd64 is warmly welcome to
try to build it and contact developers

Firebird3 (vulcan code name) will work on more arhitectures

Quoting From Vulcan Overview

Vulcan had four primary goals.
• Portability: Vulcan was developed simultaneously on four platforms: 32 bit
Windows using the Microsoft compiler from Visual Studio 7, 32 bit Linux and 64
bit Linux for AMD64/Opteron using various versions of gcc, and 64 bit Solaris
using the Sun Forte C++ compiler. Ports exist to 64-bit MVS UNIX, Itanium, and
AIX. See the Portability section.

Portability
Firebird
Firebird V1.5 and V2.0 are sensitive to minor variations in C++ compilers, which is a
serious liability given the somewhat cavalier attitude of compiler developers toward
version-to-version compatibility.
Vulcan
Vulcan was developed on four compilers simultaneously: gcc 2.96, gcc 3.3.4,
Solaris/Forte 5.5, and Microsoft VC7. To make that work, Vulcan eliminated the
dependency on std.lib, minimized all other dependencies outside the core clib (c library),
and reduced the complexity of template usage

..::firebird::..::debian::..::ubuntu::..