problem in loading midi python module

[address@hidden]

Hi, I have a problem . I have installed a precompiled   lilypond rmp on a 
Mandrake Linux 9.1 .

I was running midi2ly and I got the following message :

 Traceback (most recent call last):
  File "/usr/bin/midi2ly", line 43, in ?
    import midi
ImportError: No module named midi

It seems that the midi module can not nbe loaded .
Into the file midi2ly there are some paths to 
some libraries and I do not have them. The program
is installed under /usr/share/lilypond/<version>
and I do not have any /usr/lib/lilypond directory.
I have changed the path into the midi2ly , but nothing changed. 

Do you have any idea how to fix this problem ,
thanks Riccardo