The Collaborative International Dictionary of English v.0.48:

Talebearer \Tale"bear`er\ (t[=a]l"b[^a]r`[~e]r), n.
   One who officiously tells tales; one who impertinently or
   maliciously communicates intelligence, scandal, etc., and
   makes mischief.
   [1913 Webster]

         Spies and talebearers, encouraged by her father, did
         their best to inflame her resentment.    --Macaulay.
   [1913 Webster]

WordNet (r) 3.0 (2006):

talebearer
    n 1: someone who gossips indiscreetly [syn: tattletale,
         tattler, taleteller, talebearer, telltale,
         blabbermouth]