as I stated in the post above:

But the datasheet has mentioned that as an output, port 0 can sink 8 TTL inputs. Do I still need pullup resistor ?

No, not if you are using common anode LCDs

Port 0 is open drain and can only sink current.
You need pullup resistors if the port, as an output, is to supply current.

When used as input no resistors are needed if the port 0 pin is connected to a device that can both sink and supply current; however if the output from the device is open drain/collector a pullup is needed.

read the three 80C51_FAM_*.pdf documents. found at
http://www.semiconductors.philips.com/products/...other.html

Have fun,

Erik