Description on bind message

In manual of "48.5. Message Formats" section, there is a description
of "Bind" message.

Int16[C]   The parameter format codes. Each must presently be zero (text) or one (binary).

This could be completely non-existent field in the current
implementation of PostgreSQL. I think the fact is not very clear from
the description. It would be nice the description is something like:

Int16[C]   The parameter format codes. Each must presently be zero (text) or one (binary).This field does not exist if
thenumber of prameter values is 0.
 

Same thing can be said to following:

Int16[R]   The result-column format codes. Each must presently be zero (text) or one (binary).
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp