Error when Installing

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    -e 's,@includedir_server@,/usr/local/pgsql/include/server,g' \
    -e 's,@libdir@,/usr/local/pgsql/lib,g' \
    -e 's,@pkglibdir@,/usr/local/pgsql/lib,g' \
    -e "s,@configure@,$configure,g" \
    -e 's,@version@,7.2.1,g' \
  pg_config.sh >pg_config
chmod a+x pg_config
gmake[3]: Leaving directory `/download/postgresql-7.2.1/src/bin/pg_config'
gmake[3]: Entering directory `/download/postgresql-7.2.1/src/bin/pgaccess'
sed -e 's,@WISH@,/usr/bin/wish,g' \
    -e 's,@PGACCESSHOME@,/usr/local/pgsql/share/pgaccess,g' \
    -e 's,@PGLIB@,/usr/local/pgsql/lib,g' \
    -e 's,@DEF_PGPORT@,5432,g' \
  pgaccess.sh >pgaccess
chmod a+x pgaccess
gmake[3]: Leaving directory `/download/postgresql-7.2.1/src/bin/pgaccess'
gmake[3]: Entering directory `/download/postgresql-7.2.1/src/bin/pgtclsh'
/bin/sh mkMakefile.tkdefs.sh '/usr/lib/tkConfig.sh' 'Makefile.tkdefs'
/bin/sh mkMakefile.tcldefs.sh '/usr/lib/tclConfig.sh' 'Makefile.tcldefs'
gmake[3]: Leaving directory `/download/postgresql-7.2.1/src/bin/pgtclsh'
gmake[3]: Entering directory `/download/postgresql-7.2.1/src/bin/pgtclsh'
gmake -C ../../../src/interfaces/libpgtcl all
gmake[4]: Entering directory `/download/postgresql-7.2.1/src/interfaces/libpgtcl'
gmake -C ../../../src/interfaces/libpq all
gmake[5]: Entering directory `/download/postgresql-7.2.1/src/interfaces/libpq'
gmake[5]: Nothing to be done for `all'.
gmake[5]: Leaving directory `/download/postgresql-7.2.1/src/interfaces/libpq'
gmake[4]: Leaving directory `/download/postgresql-7.2.1/src/interfaces/libpgtcl'
gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations -I../../../src/interfaces/libpgtcl -I../../../src/include  -I/usr/X11R6/include  -c -o pgtclAppInit.o pgtclAppInit.c
gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations pgtclAppInit.o -L../../../src/interfaces/libpgtcl -lpgtcl -L../../../src/interfaces/libpq -lpq -L/usr/lib -ltcl8.3 -ldl  -lieee -lm  -Wl,-rpath,/usr/local/pgsql/lib -lcrypt -lresolv -lnsl -ldl -lm -lbsd  -o pgtclsh
gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations -I../../../src/interfaces/libpgtcl -I../../../src/include  -I/usr/X11R6/include  -c -o pgtkAppInit.o pgtkAppInit.c
In file included from pgtkAppInit.c:15:
/usr/include/tk.h:83:29: X11/Xlib.h: No such file or directory
gmake[3]: *** [pgtkAppInit.o] Error 1
gmake[3]: Leaving directory `/download/postgresql-7.2.1/src/bin/pgtclsh'
gmake[2]: *** [all] Error 2
gmake[2]: Leaving directory `/download/postgresql-7.2.1/src/bin'
gmake[1]: *** [all] Error 2
gmake[1]: Leaving directory `/download/postgresql-7.2.1/src'
gmake: *** [all] Error 2
[root@R_MICRO_2 postgresql-7.2.1]#
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