Hello !
I tried to use dosbox on my powermac g5 dual 2ghz mac os X 10.3.2 but I really don't understand how to make it work !!!
I double click on "dosbox" and the "Terminal" opens and writes:

[myaddress:~/Desktop/DOSBox_OSX] dom% /Users/myname/Desktop/DOSBox_OSX/dosbox; exit
dyld: /Users/myname/Desktop/DOSBox_OSX/dosbox can't open library: /sw/lib/libSDL-1.2.0.dylib (No such file or directory, errno = 2)
Trace/BPT trap
logout
[Opération terminée]

???? Probably something is missing.
Can you help ?
Thanks