The Collaborative International Dictionary of English v.0.48:

Addle-brained \Ad"dle-brained`\, Addle-headed \Ad"dle-head`ed\,
Addle-pated \Ad"dle-pa`ted\, a.
   Dull-witted; stupid. "The addle-brained Oberstein." --Motley.
   [1913 Webster]

         Dull and addle-pated.                    --Dryden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

addlepated
    adj 1: stupid and confused; "blathering like the addlepated
           nincompoop that you are"; "a confused puddingheaded,
           muddleheaded fellow"- Isaac Sterne [syn: addlebrained,
           addlepated, puddingheaded, muddleheaded]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "addlepated":
   addlebrained, addled, addleheaded, beclouded, befuddled,
   blear-witted, cloudy, dizzy, fogged, foggy, fuddlebrained, fuddled,
   hazy, in a fog, in a muddle, misted, misty, muddled, muddleheaded,
   muddybrained, muzzy, puzzleheaded, scramblebrained