how to make doc disk

Can anybody please let me know how to make doc disk for qnx6.2.1? I made a booting disk using doc-md2202-b128,ver5.1.2 to format and partition this doc, but when I do dformat after starting with this booting disk, I got error 26. If I load devb-doc, still got error something like allolue() failed, but I am not quite sure. I really appreciate if anybody can help me to make such a doc disk.

Thanks in advance