sendmail 설치시 err

sun os5.7, solaris7에서

semail설치시 압축풀고 나서 build시키면

Making all in:
/tmp/sendmail-8.11.0.Beta3/libsmutil
Configuration: pfx=, os=SunOS, rel=5.7, rbase=5, rroot=5.7, arch=sun4, sfx=, variant=optimized
Using M4=/usr/ccs/bin/m4
Creating ../obj.SunOS.5.7.sun4/libsmutil using ../devtools/OS/SunOS.5.7
Making dependencies in ../obj.SunOS.5.7.sun4/libsmutil
if [ -r /usr/include/sysexits.h ];
then
        ln -s /usr/include/sysexits.h;
fi
gcc -M -I. -I../../sendmail   -I../../include -DNDBM -DNIS -DNISPLUS -DMAP_REGEX -DSOLARIS=20700 -DNOT_SENDMAIL  debug.c errstring.c lockfile.c safefile.c snprintf.c strl.c   >> Makefile
In file included from ../../sendmail/sendmail.h:43,
                 from debug.c:15:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from debug.c:15:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../sendmail/sendmail.h:43,
                 from errstring.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from errstring.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../sendmail/sendmail.h:43,
                 from lockfile.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from lockfile.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../sendmail/sendmail.h:43,
                 from safefile.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from safefile.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../sendmail/sendmail.h:43,
                 from snprintf.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from snprintf.c:18:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../sendmail/sendmail.h:43,
                 from strl.c:15:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from strl.c:15:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
*** Error code 1
make: Fatal error: Command failed for target `depend'
Current working directory /tmp/sendmail-8.11.0.Beta3/obj.SunOS.5.7.sun4/libsmutil
Making in ../obj.SunOS.5.7.sun4/libsmutil
gcc -O -I. -I../../sendmail   -I../../include -DNDBM -DNIS -DNISPLUS -DMAP_REGEX -DSOLARIS=20700 -DNOT_SENDMAIL   -c  debug.c
In file included from ../../sendmail/sendmail.h:43,
                 from debug.c:15:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
In file included from ../../include/sendmail/sendmail.h:25,
                 from ../../sendmail/sendmail.h:50,
                 from debug.c:15:
/usr/include/string.h:39: string/string.h: 해당 파일이나 디렉토리가 없음
*** Error code 1
make: Fatal error: Command failed for target `debug.o'
Current working directory /tmp/sendmail-8.11.0.Beta3/obj.SunOS.5.7.sun4/libsmutil
*** Error code 1
make: Fatal error: Command failed for target `all'

이런 err메세지가 뜨는군여....

제가 어떤 실수를 했는지 아시는 분 답변좀 부탁드립니다.