Make *Completions* buffer current

[Miguel Guedes]

Is it possible to setup a hook such that whenever the *Completions* 
window is shown it is automatically made the current buffer? Whereas 
most packages part of Emacs seem to display this sort of behaviour - 
i.e. show *Completions* then make it current - some packages, such as 
Semantic, don't.

For instance, invoking semantic-ia-complete-symbol results in the 
*Completions* window being open but the window focus not changed. It's 
an annoyance having the *Completions* buffer open after one has the 
information required, in place of the buffer it replaced and not having 
the option to hit q to close it (and restore the previous window layout) 
- unless you first switch to it, then C-x k it, which becomes very time 
consuming after a while and boring.

I've tried hooking to temp-buffer-show-hook but that didn't work as the 
*Completions* buffer is current when the hook is run anyway.

Would very much appreciate it if someone knows of an elegant way of 
enforcing the behaviour desired above!

--
Miguel