Hi,
MS CRM doesn't have sms as out of box feature, however you can buy third party CRM addons which you can integrate with CRM.
Please refer the following links
http://www.netsize.com/NewsEvents_Press_20093006_Netsize-releases-SMS-plug-in-for-Microsoft-Dynamics-CRM.htm
http://www.sms-integration.com/
http://www.sms-integration.com/p_86-msdynamics-setup-instructions-sms.html
http://smsintegration.codeplex.com/
http://boomerangsms.codeplex.com/
Thomas T(MCBMSS)
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