[beagleboard] how to use gadget zero driver on beagleboard

Hi,
I want to use Gadget Zero driver on beagleboard C4.

I am able to generate the g_zero.ko, gadgetfs.ko, g_serial.ko modules, but g_zero.ko fails to insert (no udc) when copied to mmc and insmod at same directory.
My environment contains Ubuntu 10.10 32-bit, kernel 2.6.28-omap1 (built without extraversion) taken from http://gitorious.org/projects/beagleboard-diagnostic-kernel .

The configuration snapshot is as below.

CONFIG_USB_GADGET=y
CONFIG_USB_GADGET_DEBUG=y
CONFIG_USB_GADGET_DEBUG_FILES=y
CONFIG_USB_GADGET_DEBUG_FS=y
CONFIG_USB_GADGET_VBUS_DRAW=2
CONFIG_USB_GADGET_SELECTED=y

CONFIG_USB_GADGET_DUMMY_HCD=y
CONFIG_USB_DUMMY_HCD=m
CONFIG_USB_GADGET_DUALSPEED=y
CONFIG_USB_ZERO=m
CONFIG_USB_ETH=m
CONFIG_USB_ETH_RNDIS=y
CONFIG_USB_GADGETFS=m
CONFIG_USB_FILE_STORAGE=m
CONFIG_USB_G_SERIAL=m
CONFIG_USB_MIDI_GADGET=m

CONFIG_I2C=y
CONFIG_I2C_BOARDINFO=y
CONFIG_I2C_CHARDEV=y
CONFIG_I2C_HELPER_AUTO=y
CONFIG_I2C_OMAP=y

CONFIG_USB_OTG_UTILS=y
CONFIG_USB_GPIO_VBUS=y
CONFIG_ISP1301_OMAP=y
CONFIG_TWL4030_USB=y

CONFIG_USB_OHCI_HCD=y

CONFIG_USB_SUPPORT=y
CONFIG_USB_ARCH_HAS_HCD=y
CONFIG_USB_ARCH_HAS_OHCI=y
CONFIG_USB_ARCH_HAS_EHCI=y
CONFIG_USB=y

The omap_udc.ko fails to generate due to config overridding, when tried to use config:

CONFIG_USB_GADGET_OMAP=y or m, this selection gets overridden in .config and becomes not set.

I depend on support of community.