Lmb162A LCD not displaying any data with PIC16f877a !!!

Hey
I want to display characters on LCD using pic16f877a using CCS compiler and flex_lcd.c driver and 20MHZ xtal.Im using 4 bit data lines at portD and the Rs and EN connected to PortA with RW connected to ground.
The problem is that the circuit works on proteus well but when i connect it on test board its not working and its driving me crazy
Can the problem b with the 20MHz or it doesnt matter?

I take it you are making sure that the PortA pins are set as digital outputs?

Are you using RA4? if so you will need a pullup.....5k or so.

What is ADCON1 set to ?

Lastly... Ensure OSC is set to HS... It wont work with XT setting.