Very interesting and similar to my experiencei have had problems with wifi on nearly every ics-rom with different radio/modem until i flashed jvu-modem again in the end, and that finally did the magic, dunno why or how, but since then everything worked liked charm.
so long story short, if i were you i would try flashing different modems til wifi is working as it is supposed to, maybe start with jvu, cause it is an overall good modem/radio, and if jvu doesn't work as it should, move on to others till you have everything working
My problem begun nearly in the same period as my ics attempt
My other problem is that i already tested jvu, jvt,jvw,nexus modem and a few more without good result
Maybe time for me to reflash stock to see if it helps
To my Italian prefered team after juventus: congrats & thx for new tiramisu
Sent from my GT-I9000 using XDA