Does anybody know how to get a multi-page music score in PDF onto a Sony PRS-505 ebook reader in a format you can actually read?

Viewing the PDF on the device gives me "Protected page" when I try to look at anything, and Calibre's EPUB conversion doesn't seem to work (the first page is the music with random bits missing and thereafter it's odd bits of text taken from the file, no graphics).

I have both PPC and Intel Macs running Mac OS 10.4.11.