NLS_NUMERIC_CHARACTER problem

Hi all,
I have a problem in Oracle Applications.It s related with the NLS_NUMERIC_CHARACTERS.
No matter what i tried,the application doesnt recoqnize the changed NLS_NUMERIC_CHARACTER set to ".," in the enviroment file on the application server,and it always uses ",." as default.
-I set the nls_numeric_character to ".," in the .env files and bounce all of the application services but it didnt help.It still recoqnize nls_character_set as ".,"
-I set the site value of nls_character_set to ".," . It helped ,but then every report,form and everything has been changed to ".,".

In Brief, I want only our concurrent programs to use NLS_CHARACTER_SET ".," as default and all the rest of the application(site) to use ",."

I hope you can help me,
Thank and regards:cool: