64bit PPC build for MacOSX

Someone asked me why there wasn't a 64bit version of Firebird for MacOS powerpc... so I tried a build on the powerpc MacOSX box we have...
sw_vers -productVersion = 10.4.11
Build fails when we try to build config_root.cpp.

/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:272: error: typedef 'ExceptionHandlerProcPtr' is initialized (use __typeof__ instead)
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:272: error: 'ExceptionInformation' was not declared in this scope
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:272: error: 'theException' was not declared in this scope
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:306: error: 'ExceptionInformation' was not declared in this scope
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:306: error: 'theException' was not declared in this scope
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:307: error: expected primary-expression before 'userUPP'
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/MachineExceptions.h:307: error: initializer expression list treated as compound expression
/System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Headers/fp.h:1338: error: 'SIGDIGLEN' was not declared in this scope


Some googling explains what the problem is. Seems MacOSX is 10.4 is not 100% 64bit friendly and the carbon framework will not support a full 64bit build until MacOSX 10.5.

We use the carbon framework in a few, but very specific places, mainly to load UDF libraries as bundles and also the fbintl library.

So....

I either need to upgrade our powerpc Mac to MacOSX 10.5 to do the build...
or
Anybody out there got a powerpc Mac running MacOSX 10.5 that I could use to check the build?