Mac OSX Leopard and midi

[Padmavyuha]

Hello there

Using Lilypond v2.12.2-1 on an intel mac running OSX 10.5.6, using  
Smultron with the following command to generate the .ps, .pdf and .mid  
files:

~/Applications/LilyPond.app/Contents/Resources/bin/lilypond -o %%d%%p

I gewt the following output every time:

Preprocessing graphical objects...
Finding the ideal number of pages...
Fitting music on 1 page...
Drawing systems...
Layout output to `satb.ps'...
Converting to `./satb.pdf'...
warning: cannot find file: `'
error: failed files: ""

...and no midi file - the .ps and .pdf files are generated fine.

Any ideas why I'm not getting midi, and is the error message relevant  
to that, or is it to do with something else entirely?

- Padmavyuha