Same problem.
Trying to build kernel module for usb-lan adapter.

>insmod mcs7830.ko
insmod: error inserting 'mcs7830.ko': -1 Invalid module format

> dmesg | tail -1
[19219.022216] mcs7830: no symbol version for struct_module

self-compiled module:
>modinfo mcs7830.ko
filename: mcs7830.ko
license: GPL
description: USB to network adapter MCS7830)
srcversion: C2F18B78D3F943388815966
alias: usb:v0DF6p0021d*dc*dsc*dp*ic*isc*ip*
alias: usb:v9710p7730d*dc*dsc*dp*ic*isc*ip*
alias: usb:v9710p7830d*dc*dsc*dp*ic*isc*ip*
depends: usbnet,mii
vermagic: 2.6.28.10power46 preempt mod_unload modversions ARMv7

installed kernel's module:
>modinfo /lib/modules/2.6.28.10power46/mii.ko
filename: /lib/modules/2.6.28.10power46/mii.ko
license: GPL
description: MII hardware support library
author: Jeff Garzik <jgarzik@pobox.com>
srcversion: 16DCEDEE4B5629C222C352D
vermagic: 2.6.28.10power46 preempt mod_unload modversions ARMv7

What i've missed?