Hi, I just tried the kernel 3.2.0-0.bpo.3-686-pae from squeeze backports and wake-on-lan is working again on the system without problems like with 2.6.26 before.
Although the bug is not really fixed in squeeze, I have a valid workaround (using the old kernel as before is more a kind of a hack...) and there is a high chance that the bug is gone in wheezy. Bye, Mark