"I've been looking to see if I can get one or two leaders in.
"Paul is a player who I have had my eye on for a couple of weeks - since I came in - but for whatever reason we just couldn't quite get it over the line.
"Now we've been able to do that I'm delighted. This is a great club for him and it gives us a chance to have a look at him with a view to next season."
Paul har tilldelats tröja nummer 33 och är spelklar inför kvällens Derby borta mot Hull City. Han är därmed Warnocks andra värvning, följt av anfallaren Danny Webber som tidigare anslöt på en free transfer.
Samtidigt har målvakten Paul Rachubka lånats ut till Leyton Orient.