Is --protective-msdos-label incompatible with -isohybrid-mbr?

[Martin Whitaker]

I'm building a hybrid ISO using isolinux for MBR boot with this command 
line:

xorriso -as mkisofs \
  -U -J -joliet-long -r -v \
  -b isolinux/isolinux.bin \
  -c isolinux/boot.cat \
  -no-emul-boot \
  -boot-load-size 4 \
  -boot-info-table \
  -isohybrid-mbr /usr/lib/syslinux/isohdpfx.bin \
  -iso_mbr_part_type 0x17 \
  --protective-msdos-label \
  -o boot.iso \
  boot_iso

On booting from a USB stick, I get the error message:

  isolinux.bin missing or corrupt.

If I remove the --protective-msdos-label option, it boots successfully.

I tried using isohdppx.bin in place of isohdpfx.bin, but that didn't help.