[plt-scheme] PLaneT require form

The manual seems to say that this should be equivalent:
(require (planet "soegaard/bit-io/bit-io.scm"))
(require (planet "bit-io.scm" ("soegaard" "bit-io.plt" 2 0)))

Unfortunately the first one throws this:
open-input-file: cannot open input file: "/Users/jpc/Library/PLT 
Scheme/planet/300/4.1.1/cache/soegaard/bit-io.plt/2/0/bit-io.scm.ss" (No 
such file or directory; errno=2)

The manual says that it should use .scm as the extension when I use the 
string (and not the symbol) form.

Is this a bug or am I missing something?

-- 
regards,
Jakub Piotr Cłapa