using custom script to compile

[polisbul]

since I have some problems to compile by the default codeblocks command line (option -lrt doesn't work...), while I can compile with an .sh script, how can I set codeblocks to call that script when I press F9 for compiling and run?
thank you!

[BlueHazzard]

maybe: Project->Properties->Project Settings->This is a custom Makefile