LCD creates spaces while pirnting

HI all,
I am making a small project in which i am using a 3.7v li-ion 2600mah Battery, 20x4 LCD, step up converter, mosfet, 89S52 and a keypad.
my concept is to just print a command on LCD.
so for that i wrote a command like...
Code:
printscreen("HELLO WORLD, HOW ARE YOU");
i prints absolutely fine. but the problem is it prints giving spaces in between like....
HELLO WOR LD, HOW ARE Y OU.
why is it happing.
i have connected my 89s52 directly to the battery so it keeps it always on. on keypress from keypad the stepup converter gets activated using a mosfet and supplies 5v only to LCD. data pins of LCD are connected to port1 of 89S52.

it prints perfectly in proteus without giving any spaces..... but it creates problem while i try to run the same in my circuit.

do the length of the wires that i have connected my LCD and 89s52 creates a problem. i have two set of cable wires one 200mm long and one is 125mm long.... when i connect 200mm long wires the problem occurs.... but it works well with the shorter wire...

Length of tracks or wires depends on drive strength of controller I/O pin. If you need more length on LCD signals then better add a buffer on the signals going to LCD.

Your problem may be the mismatch of a 3.7 volt micro and a 5 volt LCD.
The buffer Ajay suggested should take care of that.
In could also be a timing problem.. trying to drive the LCD too fast.
What code are you using to drive the LCD ?

How smooth is the 5 volt supply ?
Try using a separate 5 volt supply as a test.