How to Enable Fast User Switching?

Is the feature of Fast User Switching available in windows XP..?
If yes, then how can I enable this feature in XP?

In Microsoft Windows XP, the Fast User Switching feature allows multiple user accounts to be logged on to a computer simultaneously. With Fast User Switching, users can switch sessions without closing Windows, programs, and so forth.
For example, User A is logged on and is browsing the Internet, User B wants to log on to their user account and check their e-mail account. User A can leave their programs running while User B logs on and checks their e-mail account. User A can then return to their session where their programs would still be running.

To enable Fast User Switching, you must also enable the Use the Welcome screen option. This feature cannot be used if your computer is a member of a domain.To enable Fast User Switching:

• Log on to the computer as an administrator.
• Click Start, click Control Panel, and then click User Accounts.
• Click Change the way users log on or off.
• If it is not already selected, click to select the Use the Welcome screen check box.

NOTE: The Use Fast User Switching check box is unavailable until you click to select the Use the Welcome screen check box.

• Click to select the Use Fast User Switching check box, and then click Apply Options. Quit the User Accounts tool.

Yes... there is a feature called Fast User Switching in XP.
To activate :

Log in as Administrator...Click on Start >> Control Panel >> User Accounts >> Change the Way Users Log On and Off >> Click Use Fast User Switching >> Click Apply Options >> Fast User Switching is now enabled.

Windows XP offers you the option of Fast User Switching.
It is very handy if you’re busy on the computer when another user wants to take a quick peek at their e-mail, documents, etc. But don’t worry! You don’t have to close out all your programs or log off. In XP, you can switch to the other user’s account and then back to your own, without ever losing anything.

Note: You can only activate the Fast User Switching option if you have a computer Administrator account.

First, you need to go to Start, Control Panel and click on the User Accounts link. Once there, click on the User Accounts link one more time and then choose the option of "Change the way users log on or off." Lastly, in the next window, you can see whether or not the Fast User Switching option is enabled. If it's not, you can enable it by simply checking the box next to it and then clicking Apply Options.