Maybe this question is a little bit strange, but some of our ASP customer complain about slow respons when they hit the @ key on there keyboard. This is only when they are loged into Windows 2003 Terminal Server (no Citrix). Actually I have seen the problem my self on another server. Often you have to hit the @ key 2-3 times before it shows.
For information in Norway we have to hit the Alt Gr+2 too get the @ symbol. Maybe there could be something problem with hit to key's at the same time over a terminal server session??