>Note that at least one machine detected the resolution correctly on 2.6.32, but no kernels I've tried before or since.
Actually now that I think about it, I believe it was 2.6.26 which worked. Before that was probably the era of massive breakage, and from there I skipped to 2.6.29 which was apparently when KMS was introduced for Intel, which seems a likely candidate for the breakage.