Sitecore for Salesforce (S4S) versions after 1.5.2011.912 add support for the following MembershipUser properties:
To use these properties the corresponding fields should be created in Salesforce for Contacts and configured against the Membership provider in the web.config.
<add name="salesforce" type="FuseIT.Sitecore.SalesforceSecurityProvider.SalesforceMembershipProvider, FuseIT.Sitecore.SalesforceSecurityProvider" readOnly="false" connectionStringName="S4SConnString" applicationName="sitecore" minRequiredPasswordLength="1" minRequiredNonalphanumericCharacters="0" passwordStrengthRegularExpression=".*" requiresUniqueEmail="false" passwordFieldName="SitecorePassword__c" userNameFieldName="SitecoreUsername__c" isEncryptedFieldName="SitecorePasswordEncrypted__c" isApprovedFieldName="SitecoreIsApproved__c" isLockedOutFieldName="SitecoreIsLockedOut__c" passwordAttemptWindow="5" lastLoginDateFieldName="SitecoreLastLoginDate__c" lastLockoutDateFieldName ="SitecoreLastLockoutDate__c" failedPasswordAttemptCountFieldName = "SitecoreFailedPasswordAttemptCount__c" failedPasswordAttemptWindowStartFieldName = "SitecoreFailedPasswordAttemptWindowStart__c" />
Once configured the Sitecore User Manager can be used to Disable/Enable a Salesforce Contact user or Unlock them.