TabletPC'Corner: Toute l'information des Tablet PC

Exclusive: Windows XP SP2 Will Include Concurrent Sessions
Windows XP Service Pack 2 (SP2) will include a long-awaited concurrency feature that will let multiple users connect simultaneously to the same PC. The feature is mysteriously absent in the current SP2 beta release, and how Microsoft will implement the feature and how many concurrent interactive users it will support is unclear, but a Microsoft representative confirmed to me this week that the concurrent sessions feature, called "multisessions" internally, is happening. The next XP Media Center Edition (MCE) version, due this fall, will use the feature to enable as many as five Media Center sessions to remote Windows Media Center Extender devices.

If you run XP sp2 beta 1, you can enable it now, the setting taken from win2k3 enables it for winXP sp2! Even Microsoft isn't aware of it.

Limit though is you need to be logged on as different user.
HKEY_LOCAL_MACHINESystemCurrentControlSetControlTer minal ServerLicensing Core
Create a new DWORD entry "EnableConcurrentSessions" and assign a value of 1 to it. Concurrent Sessions is now enabled. No need to reboot !