[otrs] Module Kernel::Modules::CustomerTicketSearch not registered in Kernel/Config.pm!

Hello, I saw several errors in the OTRS log as following, Tue Nov 10 16:28:38 2009 error OTRS-CGI-10 Module Kernel::Modules::CustomerTicketSearch not registered in Kernel/Config.pm! Tue Nov 10 16:28:36 2009 error OTRS-CGI-10 Module Kernel::Modules::CustomerTicketSearch not registered in Kernel/Config.pm! Tue Nov 10 16:28:30 2009 error OTRS-CGI-10 Module Kernel::Modules::CustomerTicketSearch not registered in Kernel/Config.pm! Could you kindly help me? Thanks you very much! Zhang QZ