Installing Realtek 8188 wireless driver fails
to solve the "linux/smp_lock.h not found" error you need to edit this two files into the archive driver/rtl8192_8188CU_linux_v3.1.2590.20110922.tar.gz
file 1: include/rtw_io.h
Change osdep_service.h (line 49) linux/smp_lock.h to linux/smp.h
file 2: include/osdep_service.h
Change file rtw_io.h (line 36) linux/smp_lock.h to linux/smp.h
blacklist rtl8192cu as well, it is the default driver, this will make the system use the new one.
I wrote a post that combined all of the solutions proposed here
http://www.r-statistics.com/2011/11/edimax-ew-7811un-usb-wireless-connecting-to-a-network-on-ubuntu-11-10/
chiicoff, icracked - you two saved my day.
(p.s: the line numbers should be reversed)