translate advice?

hello
I work on translate this hack to arabic
hope u give me permission to do that
also
it’s all depended on lang file?
cuz I have see there r will be problem with charset
from where I can change charset?
also
after I finsih translate I get this error if i click on any game
on head of page

Warning: Cannot modify header information - headers already sent by (output started at /home/*******/public_html/t/arcade/lang/lang_Arcade_ar.php:1) in /arcade.php on line 2655

Warning: Cannot modify header information - headers already sent by (output started at /home/*********/public_html/t/arcade/lang/lang_Arcade_ar.php:1) in /arcade.php on line 2656

Warning: Cannot modify header information - headers already sent by (output started at /home/*********/public_html/t/arcade/lang/lang_Arcade_ar.php:1) in /arcade.php on line 2657

Warning: Cannot modify header information - headers already sent by (output started at /home/******/public_html/t/arcade/lang/lang_Arcade_ar.php:1) in /arcade.php on line 2658

thanks in advance