When running my app on a PowerPC Mac, which has 10.3 installed, I'm getting the following crash.log

===== Mon Apr 05 1976 ===== 05:11:06 Europe/London ===== dyld: /Users/sumo/Desktop/bouncing.app/Contents/MacOS/YoYo70 Undefined symbols: /Users/sumo/Desktop/bouncing.app/Contents/MacOS/YoYo70 undefined reference to _kCGColorSpaceGenericGray expected to be defined in Carbon /Users/sumo/Desktop/bouncing.app/Contents/MacOS/YoYo70 undefined reference to _kCGColorSpaceGenericRGB expected to be defined in Carbon /Users/sumo/Desktop/bouncing.app/Contents/MacOS/YoYo70 undefined reference to _kUTTypePlainText expected to be defined in Carbon /Users/sumo/Desktop/bouncing.app/Contents/MacOS/YoYo70 undefined reference to _kUTTypeUTF16PlainText expected to be defined in Carbon /Users/sumo/Desktop/bouncing.app/Contents/MacOS/YoYo70 undefined reference to _kUTTypeUTF8PlainText expected to be defined in Carbon Apr 5 05:11:09 tobyxps crashdump: Unable to determine CPSProcessSerNum pid: 934 name: YoYo70
Apr 5 05:11:09 tobyxps crashdump: Started writing crash report to: /Users/sumo/Library/Logs/CrashReporter/YoYo70.crash.log Apr 5 05:11:09 tobyxps crashdump: Finished writing crash report to: /Users/sumo/Library/Logs/CrashReporter/YoYo70.crash.log

Will linking directly to the 10.3 SDK get around this problem, or will that break other LCL references?

I am aware that 10.4 is the preferred OS version but is there a way around this issue?

Dominique.

Will linking directly to the 10.3 SDK get around this problem, or will that break other LCL references?

No, won't work. LCL-Carbon uses routines available only in 10.4

I am aware that 10.4 is the preferred OS version but is there a way around this issue?

You can provide a patch for LCL-Carbon which ifdefs out the use of all routines which require Mac OS X 10.4 if a define is active, and then rebuild your LCL with the define. Something like
CarbonSupportMacOSX_10_3

It will work much better if you provide adequate substitutes for those calls that work in Mac OS X 10.3

You can see which calls cause trouble and use Find in Files in the IDE in the directory lcl/interfaces/carbon to find them.