how we can use multiple membership providers on the same web site

hi,how we can use multiple membership providers on the same web site i am using this code in web.config file. <roleManager enabled="true" defaultProvider="YafRoleProvider"> <providers> <clear/> <add connectionStringName="yafnet" applicationName="YetAnotherForum" name="YafRoleProvider" type="YAF.Providers.Roles.YafRoleProvider"/> <add name="DbRoleProvider" type="BlogEngine.Core.Providers.DbRoleProvider, BlogEngine.Core" connectionStringName="BlogEngine"/> </providers> </roleManager> <membership defaultProvider="YafMembershipProvider" hashAlgorithmType=" ...