suser_name() returns old logon data(instead of giving changed logon info)

[sudhivns]

Hi,
1.Initially i had user name as "User1" in Active Directory.
2. When logged into system A as "User1" queried for suser_name(), it returned "User1" as expected
3. Now in Active Directory, changes "User1" to "TestUser1" as logon name.
4. Logged onto System A as "TestUser1" and suser_name() giving "User1" instead of "TestUser1" .
5. After certain time(>5mins), suser_name() giving "TestUser1" .

Is any parameter linked connection timeout ?
why suser_name() not returning correct logon info, though i have logged into system with new logon name ?
Please help

[sudhivns]

Workaround: Restart the machine where SQL server installed.