ruby portupgrade error

[n dhert]

there was an upgrade to ruby giving error:
how to fix it?
...
cc -I/usr/include -O2 -fno-strict-aliasing -pipe  -fPIC    -DRUBY_EXPORT
-L.  -r
path=/usr/lib:/usr/local/lib -rdynamic   main.o  libruby18-static.a -lrt
-lcrypt
 -lm -L/usr/lib  -rpath=/usr/lib:/usr/local/lib  -o miniruby
libruby18-static.a(process.o)(.text+0x1b40): In function `proc_exec_v':
: undefined reference to `rb_thread_stop_timer_fake'
libruby18-static.a(process.o)(.text+0x25ad): In function `rb_proc_exec':
: undefined reference to `rb_thread_stop_timer_fake'
*** Error code 1
Stop in /usr/ports/lang/ruby18/work/ruby-1.8.7-p248.
*** Error code 1
Stop in /usr/ports/lang/ruby18.
*** Error code 1
Stop in /usr/ports/lang/ruby18.
** Command failed [exit code 1]: /usr/bin/script -qa
/tmp/portupgrade20100428-83
762-bmz4km-0 env UPGRADE_TOOL=portupgrade
UPGRADE_PORT=ruby+nopthreads-1.8.7.248
,1 UPGRADE_PORT_VER=1.8.7.248,1 make FETCH_BEFORE_ARGS=-q
DEPENDS_TARGET=package
** Fix the problem and try again.
--->  Build of lang/ruby18 ended at: Wed, 28 Apr 2010 07:09:13 +0200
(consumed 0
0:00:38)
--->  Upgrade of lang/ruby18 ended at: Wed, 28 Apr 2010 07:09:13 +0200
(consumed
 00:00:38)
--->  ** Upgrade tasks 2: 1 done, 0 ignored, 0 skipped and 1 failed
--->  Listing the results (+:done / -:ignored / *:skipped / !:failed)
        + net/openldap24-client (openldap-client-2.4.21)
        ! lang/ruby18 (ruby+nopthreads-1.8.7.248,1)     (new compiler error)
--->  Packages processed: 1 done, 0 ignored, 0 skipped and 1 failed
--->  Session ended at: Wed, 28 Apr 2010 07:09:15 +0200 (consumed 00:01:59)