Same issue here. When I remove Google ads from my pages, the certificate error is gone, so obviously AdSense triggers the certificate warnings. Anyone knows how to contact Google about this? I cannot find any email or error reporting links on their site.
I don't have IE8, obviously, but with IETester I currently get no errors. As two days have nearly passed, I assume it's been resolved.
This issue caused me to have the worsed payment day this month... how does adsense manage to stuff things up time and time again... give publishers a break... first it was panda now this...
It's not like they want to lose money (this might cost you a few dollars, to them it's possibly into the hundreds of thousands). And what's Panda got to do with this? Besides, on average IE8 has a 20% market share, if not lower, so perhaps you should look into other causes if your earnings are significantly lower.