It was previously reported (twice) that drbd-0.7.17 didn't compile under the initial releases of 2.6.17. Neither does 0.7.18.
/var/tmp/portage/drbd-0.7.18/work/drbd-0.7.18/drbd/drbd_main.c: In function `drbd_create_mempools':
/var/tmp/portage/drbd-0.7.18/work/drbd-0.7.18/drbd/drbd_main.c:1547: error: `SLAB_NO_REAP' undeclared (first use in this function)
/var/tmp/portage/drbd-0.7.18/work/drbd-0.7.18/drbd/drbd_main.c:1547: error: (Each undeclared identifier is reported only once
/var/tmp/portage/drbd-0.7.18/work/drbd-0.7.18/drbd/drbd_main.c:1547: error: for each function it appears in.)
make[3]: *** [/var/tmp/portage/drbd-0.7.18/work/drbd-0.7.18/drbd/drbd_main.o] Error 1
make[2]: *** [_module_/var/tmp/portage/drbd-0.7.18/work/drbd-0.7.18/drbd] Error 2
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