sendmail does NOT use secondary nameserver

[Claus van de Vlierd]

Hello ,

  a) in case our primary nameserver works rather slowly
     our "sendmail" does NOT automatically use  the secondary nameserver.

     BUT : in the mailer's  "/etc/resolv.conf"  there are both 
IP-addresses of the prim. and sec. nameserver
  (by the way : our browsers have no problems to switch to the sec. 
nameserver in those cases) .

  b) can anyone give me "a helping hand" how to make sure that
     "sendmail" uses for its DNS-queries on port 53 the sec. nameserver
      in case our prim. nameserver fails ?!
      (perhaps with some refined "route-statments" in the attached 
Cisco-Router
?!

   c) thank your for any help !

     regards ,  Claus van de Vlierd