EDIT: On further digging that is not the correct datasheet, and I cannot find the proper one. It is a "Data vision P73-1" 4x40. It has 4 chips silkscreened with "SEC C929 KS0063B" and 2 with "SEC C923 KS0066U-00".
I have driven an HD44780 compatible 40x4 display before. Just requires 2 enable lines - the liquidcrystal440 library can cope with it (possible the IDE bundled liquidcrystal library now - not sure).
mowcius:
That was for a 20x4 which is similar (as it uses 2 HD44780 chips) but different as it will have a different pinout.
Anyway, can we get a working datasheet link? Then we can work tell you exactly how to hook it up.
Mowcius
Gotcha!
Actually I was working with 74HC595N's today, and here is this schematic for the 40x4 connecting a Shift Register... but I don't know if he has that one.