Running just-one-space after expand-abbrev

[Ian Eure]

I have abbrevs for public/protected/private: pub/prot/pri.

I often find that I'm editing something like:

public function foo();

And I want to change it from public to protected. My first thought is:  
C-a M-d prot SPC

The problem is that the M-d leaves the whitespace to the left of  
"function," and the SPC to expand the   abbrev gives another, so now I  
have two spaces.

Is it possible to run (just-one-space) after an abbrev is expanded? I  
tried advising (expand-abbrev), but that didn't work. I don't see any  
hooks for that function, either.

Ideas?