You may need to enable DNS doctoring to get this working properly. If you're using static NAT translations you'll need to remove the NAT entry and re-enter it with 'dns' tacked on at the end.
FROM:
static (inside,outside) 66.55.12.33 192.168.1.33 netmask 255.255.255.255
TO:
static (inside,outside) 66.55.12.33 192.168.1.33 netmask 255.255.255.255 dns
After re-entering the entry you may need to clear the xlate as well.
Good luck!
James