Custom Kernel: can't load usb gadget modules

Hi all!

I’ve recently bought a Beagle Board xM Rev C and i’m trying to build my own custom kernel. I’ve done the following steps:

I’ve written (I think that rcnelson wrote it) that there’s no more specific config file for the beagleboard in arch/arm/configs/ folder . That, instead, the most suitable file for Bb should be the omap2plus_defconfig file. So i used this file to build the kernel, created my modules, installed them on the rootfs filesystem and launched Bb with the new kernel.
It seems to work correctly (no errors during the boot), but when i try to load any of the gadget modules ( ) , i get an error message.

Here an example:
beagle# modprobe -l | grep gadget

beagle# modprobe g_serial
modprobe: can’t load module g_serial (kernel/drivers/usb/gadget/g_serial.ko): No such device

It happens with any gadget module i try to install. I want to test the Beagle board as a device for my PC/Host, and i just can’t get the way to load those gadget modules. Is there something i’m missing?? (From narcissus i’ve downloaded a beagle bone version with the option “All kernel modules” checked, and it works fine). Any Patch?? another module that should be installed?? they should be built-in modules?? Any Idea??

Thank you very much for your time and attention.