Microsoft does not provide this capability natively in Active Directory.
Some third party providers have created solutions. You can try these to see if they work for you.
<a href=”http://technet.microsoft.com/en-us/magazine/2005.05.utilityspotlight.aspx”>TechNet Utility Spotlight: Limit Login Attempts With LimitLogin</a>
<a href=”http://www.isdecisions.com/products/userlock/limits-concurrent-logins.htm”>Limit concurrent logins with UserLock</a>