For People Who Specialize In Oracle Only

im using oracle 11g release 2 with operating system winodws 7 ultima

for windows i change the regonal language  

format :                           arabic 

location :    united arab emirates

adminisitrative (current language for non unicode program) or what the called also current system local:                          Arabic

 first : is the last step necessary to use oracle in arabic 

second : when i change ( current system local) to arabic the font in design layout is different than runtime  and if i make it english (runtime and design) will be the same

third question :what is mean by (current language for non unicode program) and does this mean to us oracle for arabic it will categories under non unicode 

please do not answer if you are not sure 100 % of what you are saying