fixed typo

Distribution/ParseUtils.hs

@@ -106,7 +106,7 @@ runP lineNo fieldname p s =
   where results = readP_to_S p s
 
 locatedErrorMsg :: PError -> (Maybe LineNo, String)
-locatedErrorMsg (AmbigousParse f n) = (Just n, "Ambigous parse in field '"++f++"'")
+locatedErrorMsg (AmbigousParse f n) = (Just n, "Ambiguous parse in field '"++f++"'")
 locatedErrorMsg (NoParse f n)       = (Just n, "Parse of field '"++f++"' failed: ")
 locatedErrorMsg (FromString s n)    = (n, s)