The problem not exists in the one and only 2.6.31 kernel linux-image-2.6.31-1-amd64_2.6.31-1_amd64.deb and comes up in the first 2.6.32 kernel linux-image-2.6.32-1-amd64_2.6.32-6_amd64.deb . I have also filed a bug report to bugzilla.kernel.org, bug id is 22022 . Thanks and regards Rolf