[m-rev.] for review: fix mantis bug #559, step 1

[Zoltan Somogyi]

This does not fix Mantis #559; it is just the first step
towards the fix.

For review and before-and-after benchmarking by Julien,
since it is his bug, and he has server-class machines that have
way less benchmark jitter than my laptop.

Zoltan.
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