problems with building seamonkey2-devel

[Marat N.Afanasyev]

Hello!

I'm trying to build experimental/seamonkey-devel, but get stalled in the 
same place:

gmake[3]: Entering directory 
`/usr/ports/local/seamonkey2-devel/work/comm-central/directory/c-sdk'
Makefile:42: config/autoconf.mk: No such file or directory
../../config/config.mk:57: /config/autoconf.mk: No such file or directory
Makefile:55: *** target file `depend' has both : and :: entries.  Stop.
gmake[3]: Leaving directory 
`/usr/ports/local/seamonkey2-devel/work/comm-central/directory/c-sdk'
gmake[2]: *** [tier_platform] Error 2
gmake[2]: Leaving directory 
`/usr/ports/local/seamonkey2-devel/work/comm-central/mozilla'
gmake[1]: *** [default] Error 2
gmake[1]: Leaving directory 
`/usr/ports/local/seamonkey2-devel/work/comm-central/mozilla'
gmake: *** [default] Error 2
*** Error code 1

Stop in /usr/ports/local/seamonkey2-devel.
*** Error code 1

Stop in /usr/ports/local/seamonkey2-devel.

And I don't know what to do. can you tell me, what should I look for? 
probably some required port?

# uname -a
FreeBSD xxx.xxx.xx 8.1-STABLE FreeBSD 8.1-STABLE #3: Sat Jul 24 15:48:00 
MSD 2010     root at xxx.xxx.xx:/usr/obj/usr/src/sys/ZEALOT  amd64

-- 
SY, Marat