"broken pipe" error during building of port

Hello, 

Yesterday I got latest sources of -CURRENT and upgraded my installation.
Now when I build any port "broken pipe" error message appear:

/usr/ports/mail/mutt-devel>make
===>  Vulnerability check disabled, database not found
===>  License check disabled, port has not defined LICENSE
===>  Found saved configuration for mutt-devel-1.5.21
===>  Extracting for mutt-devel-1.5.21
=> SHA256 Checksum OK for mutt/mutt-1.5.21.tar.gz.
=> SHA256 Checksum OK for mutt/patch-1.5.21.rr.compressed.gz.
=> SHA256 Checksum OK for mutt/patch-1.5.21.vvv.initials.gz.
=> SHA256 Checksum OK for mutt/patch-1.5.21.vvv.quote.gz.
===>  Patching for mutt-devel-1.5.21
===>  Applying distribution patches for mutt-devel-1.5.21
===>  Applying FreeBSD patches for mutt-devel-1.5.21
  I can't seem to find a patch in there anywhere.
===>   mutt-devel-1.5.21 depends on file: /usr/local/bin/automake-1.11 - found
===>   mutt-devel-1.5.21 depends on file: /usr/local/bin/autoconf-2.68 - found
===>   mutt-devel-1.5.21 depends on shared library: iconv.3grep: writing output: Broken pipe
grep: writing output: Broken pipe
grep: writing output: Broken pipe
grep: writing output: Broken pipe
grep: writing output: Broken pipe
grep: writing output: Broken pipe
grep: writing output: Broken pipe
grep: writing output: Broken pipe
[...]

Also error sometimes appears after executing "man something":

/home/minotaur>man muttrc
zcat: error writing to output: Broken pipe
zcat: /usr/local/man/man5/muttrc.5.gz: uncompress failed

I found thread from stable_at_ mailing list 
http://www.mail-archive.com/freebsd-stable_at_freebsd.org/msg111266.html
with same error on 8.1-RC2. The solution there is to get 'sh' sources
from previous release. I'm not sure whether it will help in my case.

Any way to solve the issue? Thanks in advance!

-- 
MINO-RIPE