Something wrong with -CURRENT? (network problems)

Since about the time of teh NEWCONS commit, freshly built kernels do not
work correctly for me. Symptoms are:

- long delays opening TCP connections (even to localhost)
- TCP transmission errors (e.g. fetchmail aborts because of short
  transfers, could be due to a timeout being triggered)

I first noticed this during multi-user startup, since some of the
daemons took tens of seconds to start (especially bad is SpamAssasin),
instead of fractions of a second.

At first I thought this could be caused by testing NEWCONS, but the
symptoms of a kernel with SCONS are identical.

Kernel configuration and other parameters are unchanged.

I do not have time to bisect the commits, but just wanted to ask whether
this is a general problem with -CURRENT, or only affects my test system
(my local file-, media-, mail-, and web-server).

(I might have time to bisect revisions during the week-end, though.)

System information:

i7-2660, N67 chipset, 24GB RAM, amd64

ZFS only configuration (ZRAID1, 4*2TB)

Kernel config is just a stripped down generic (removing all unnecessary
devices) with the following KLDs loaded:

Id Refs Address            Size     Name
 1   25 0xffffffff80200000 e0efe8   kernel
 2    1 0xffffffff8100f000 22dd88   zfs.ko
 3    2 0xffffffff8123d000 5b68     opensolaris.ko
 4    1 0xffffffff81412000 1478     fdescfs.ko
 5    1 0xffffffff81414000 c250     ipfw.ko
 6    1 0xffffffff81421000 3923     linprocfs.ko
 7    1 0xffffffff81425000 999      linsysfs.ko

Kernel based on SVN rev. 258894 works reliably with latest world.

The kernel I built after seeing the initial NEWCONS commits (still
with SCONS) worked, but shortly thereafter, when I tried NEWCONS, the
symptoms started (but persisted after going back to SCONS).

I just checked SVN rev 259250 and the problem persists (without NEWCONS
configured into the kernel).

So my questions are:

- is anybody else affected or is this a local problem?

- has there been a commit that touched the network stack or might
  cause the observed delays?

Thanks in advance fpr any insight you might be able to offer!

Regards, STefan