Stucking processes

Hello all.
Since I'm using stable as host, and current in chroot, I'll write to
both mail list, sorry for any inconvenience.

My host is binary freebsd-updated 9;
FreeBSD 9.0-RELEASE-p3 (GENERIC) #0: Tue Jun 12 02:52:29 UTC 2012

I have chroot with latest current there installed r237089 (make
buildworld && buildkernel, no specific flags)
When I built from ports some programs in chroot all went fine, until I
got stucked process automoc (when building kdelibs4);
After few restarts I got build, and forget about it.
I'm toying now with portupgrade, and see similar stucks in ruby18 and
ruby19 (Even got few times in miniruby while building 1.8);

Here's example of stucked processes (they aren't in top, and seems
totally inactive. I haven't kill them yet, so can try to dig, but to
where?):
 2677   5  Is    0:00,00 | `-- /bin/sh
 2678   5  I     0:00,00 |   `-- sudo su
 2679   5  I     0:00,00 |     `-- su
 2680   5  I     0:00,01 |       `-- _su (csh)
 2687   5  I     0:00,03 |         `-- /bin/csh -i
 2690   5  I+    0:04,34 |           `-- ruby19: portupgrade: [1/237]
audio/libsamplerate (ruby19)

#  procstat -k 2690
  PID    TID COMM             TDNAME           KSTACK
 2690 100477 ruby19           -                mi_switch
sleepq_catch_signals sleepq_timedwait_sig _sleep do_wait
__umtx_op_wait_uint_private_compat32 ia32_syscall Xint0x80_syscall
 2690 101110 ruby19           -                mi_switch
sleepq_catch_signals sleepq_wait_sig _cv_wait_sig seltdwait
kern_select freebsd32_select ia32_syscall Xint0x80_syscall

#top (with inactive filtered out;)
last pid: 11049;  load averages:  0.09,  0.16,  0.19

                                        up 0+00:14:48  12:27:20
63 processes:  1 running, 62 sleeping
CPU:  1.0% user,  0.0% nice,  0.8% system,  1.2% interrupt, 97.0% idle
Mem: 184M Active, 96M Inact, 1104M Wired, 2412K Cache, 171M Buf, 454M Free
Swap: 4096M Total, 4096M Free

  PID USERNAME    THR PRI NICE   SIZE    RES STATE   C   TIME   WCPU COMMAND
 2610 root          2  20    0   261M 82548K kqread  1   0:12  1.27% rtorrent


Is this my side's problem, or there's something wrong with current? :)
Any help appreciated.

-- 
Regards,
Alexander Yerenkow