You are 100% correct
I wont say im not interested about injection rates , but for now it will be great to have it just working.

I compiled module from kernel-power-2.6.28...
Im not 100% sure i've it correcly so here is what i did.

1. from scratchbox i downloaded kernel source:
[sbox-MaemoKernel: ~/maemo_kernel] > apt-get source kernel-power

2. I entered kernel-power folder and copied default config:
[sbox-MaemoKernel: ~/maemo_kernel/kernel-power-2.6.28] > cp debian/rx51power_defconfig arch/arm/configs/
[sbox-MaemoKernel: ~/maemo_kernel/kernel-power-2.6.28] > make EXTRAVERSION=$(dpkg-parsechangelog | sed -ne 's/^Version: .*-maemo\(.*\)/.10power\1/p') rx51power_defconfig

3. I edited .config and discomented "CONFIG_RTL8187 is not set" to "CONFIG_RTL8187=m" i think its a good idea to compile it as module:
#
# Wireless LAN
#
# CONFIG_WLAN_PRE80211 is not set
CONFIG_WLAN_80211=y
# CONFIG_LIBERTAS is not set
# CONFIG_LIBERTAS_THINFIRM is not set
# CONFIG_USB_ZD1201 is not set
# CONFIG_USB_NET_RNDIS_WLAN is not set
CONFIG_RTL8187=m
# CONFIG_MAC80211_HWSIM is not set (im not sure if its necesary, i think not)

4. Including changes for compilation.
[sbox-MaemoKernel: ~/maemo_kernel/kernel-power-2.6.28] > make EXTRAVERSION=$(dpkg-parsechangelog | sed -ne 's/^Version: .*-maemo\(.*\)/.10power\1/p') oldconfig

5. Compiling modules
[sbox-MaemoKernel: ~/maemo_kernel/kernel-power-2.6.28] > make EXTRAVERSION=$(dpkg-parsechangelog | sed -ne 's/^Version: .*-maemo\(.*\)/.10power\1/p') modules

Once compiled i took the module apart and tried to insmod it, here is dmesg output:
[ 9536.131896] rtl8187: no symbol version for struct_module

I have not provide any external power source such as a powered hub, i think h-e-n provides itself enough power, anyway i will try one.

Thanx for helping