I have downloaded both 1.5.8-java6 and 1.5.8-java7, neither works on Mac OSX, but with different problem.
The test project is Basics-> Blink
1.5.8-java6 version, arduino cannot start even, running arduino.app and it exited immediately. Console reported it returned with error status 1
1.5.8-java7 version IDE started fine, but cannot compile, I selected board arduino uno, and click verify, it complained:
avr-g++: internal compiler error: Segmentation fault: 11 (program cc1plus)
libbacktrace could not find executable to open
Please submit a full bug report,
with preprocessed source if appropriate.
See http://gcc.gnu.org/bugs.html for instructions.
/Users/xxxx/Downloads/Arduino.app/Contents/Java/hardware/tools/avr/bin/avr-g++ returned 4
Error compiling.
I downloaded 1.0.6 version ,it worked all fine