Problem building current

Hello.
I think I have some problem building current on my system (which is not
current).
# uname -a
FreeBSD 9.0-RC1 FreeBSD 9.0-RC1 #0: Tue Oct 18 18:51:43 UTC 2011
root_at_farrell.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC amd64
# pwd
/zpool0/testenv/sources/10-kms/lib/libc

# svn info
Path: .
Working Copy Root Path: /zpool0/testenv/sources/10-kms
URL: http://svn.freebsd.org/base/head/lib/libc
Repository Root: http://svn.freebsd.org/base
Repository UUID: ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Revision: 228276
Node Kind: directory
Schedule: normal
Last Changed Author: jilles
Last Changed Rev: 228269
Last Changed Date: 2011-12-05 02:00:47 +0200 (пн, 05 дек 2011)

# make -DNO_CCACHE
cc -O2 -pipe -I/zpool0/testenv/sources/10-kms/lib/libc/include
-I/zpool0/testenv/sources/10-kms/lib/libc/../../include
-I/zpool0/testenv/sources/10-kms/lib/libc/amd64 -DNLS
-D__DBINTERFACE_PRIVATE
-I/zpool0/testenv/sources/10-kms/lib/libc/../../contrib/gdtoa -DINET6
-I/usr/obj/zpool0/testenv/sources/10-kms/lib/libc
-I/zpool0/testenv/sources/10-kms/lib/libc/resolv -D_ACL_PRIVATE
-DPOSIX_MISTAKE
-I/zpool0/testenv/sources/10-kms/lib/libc/../../contrib/tzcode/stdtime
-I/zpool0/testenv/sources/10-kms/lib/libc/stdtime
-I/zpool0/testenv/sources/10-kms/lib/libc/locale -DBROKEN_DES -DPORTMAP
-DDES_BUILTIN -I/zpool0/testenv/sources/10-kms/lib/libc/rpc -DYP
-DNS_CACHING -DSYMBOL_VERSIONING -std=gnu99 -fstack-protector
-Wsystem-headers -Werror -Wall -Wno-format-y2k -Wno-uninitialized
-Wno-pointer-sign -c
/zpool0/testenv/sources/10-kms/lib/libc/net/sctp_sys_calls.c
/zpool0/testenv/sources/10-kms/lib/libc/net/sctp_sys_calls.c: In function
'sctp_opt_info':
/zpool0/testenv/sources/10-kms/lib/libc/net/sctp_sys_calls.c:416: error:
'SCTP_REMOTE_UDP_ENCAPS_PORT' undeclared (first use in this function)
/zpool0/testenv/sources/10-kms/lib/libc/net/sctp_sys_calls.c:416: error:
(Each undeclared identifier is reported only once
/zpool0/testenv/sources/10-kms/lib/libc/net/sctp_sys_calls.c:416: error:
for each function it appears in.)
/zpool0/testenv/sources/10-kms/lib/libc/net/sctp_sys_calls.c:417: error:
dereferencing pointer to incomplete type
*** Error code 1


I'm getting this error when I'm trying to buildworld from svn checkouted
sources (e.g. I'm using plain "make buildworld", without NO_CLEAN or some
else).

Any ideas why it is happening?
-- 
Regards,
Alexander Yerenkow