when you built for i386 against SDK 10.5 this will fail as
does not exist in the SDK.
I solved this by adding OS X 10.5 to the USE_DEPRECATED_COREAUDIO_API definition by changing
#if TARGET_CPU_PPC || TARGET_CPU_PPC64 || !defined(MAC_OS_X_VERSION_10_6)
#if (MAC_OS_X_VERSION_MAX_ALLOWED < 1060)
This might need fine tuning since the new way to load a soundfont is valid for 10.5 but not <10.5...