reconfirm

from WordNet (r) 3.0 (2006)

reconfirm
    v 1: confirm again; "You must reconfirm your flight
         reservations"

from The Collaborative International Dictionary of English v.0.48

Reconfirm \Re`con*firm"\ (r[=e]`k[o^]n*f[~e]rm"), v. t. [Pref.
   re- + confirm: cf. F. reconfirmer.]
   To confirm anew. --Clarendon.
   [1913 Webster]