Error install Conexant HCF modem drivers (hcfpcimodem-1.03) Work on kernel-2.6.10 but error on kernel-2.6.11-rc1 I think something has been changed in kernel-2.6.11-rc1 . On kernel-2.6.10 work well. Kernel is make with CONFIG_SERIAL_CORE enabled. hcfpcihw: Unknown symbol cnxthcf_cnxt_serial_add hcfpcihw: Unknown symbol cnxthcf_cnxt_serial_remove