I think what he is asking for is something different... he wants those keywords to be magically replaced when a file is saved, every time. Much in the sense of what a source control system does when you update.
The only keyword substitution that is supported by Code::Blocks is the one described by Pecan and Morten, and it only works for the current word (thus, you cannot simply type 3 dozen keywords and hit Ctrl-J once, it doesn't work that way). This is deliberate, too, as it might otherwise terribly mess up your sources.