error with lilypond-book

[Dr. med. Kai Lautenschläger]

Hi all,

I am trying to get my way into lilypond-book. After reading the manual, I 
started and got the following error (using \version 2.15.40 with jEdit5.0pre1 
on a Mac with OS 10.7.4) when I invoke lilypond-book: (command: 
lilypond-book.py --format=latex %buffer)

"Error running external command.
See the activity log about the problem.
Cannot run program "/Applications/Lilypond.app/Contents/Resources/bin/python" 
(in directory "Users/[…]/Documents/02_Musik"): error=2, No such file ore 
directory"

Even when I move python in the wanted directory or change the directory in the 
jEdit Plugin Options ore change the command for invoking lilypond-book the 
error message will stay the same. Can anyone give me a clue, where to start 
with solving?

I'd be grateful!!!

Kai