SQL displaying unicode international characters as ??

Last week I had a problem with MSSQL, all international characters, like Korean and Japanese were displaying ??. I tried to insert them directly into the DB instead of doing it using PHP or ColdFusion, but to no avail. Inserting a N before the characters solved the problem. For eg,

update table myTable
val = N'텍스트와 웹페'
where cond1=cond2;

That solved the problem, but that is not a very good solution. There is an option in MSSQL server that needs controls unicode characters.