Support for S/390.
diff --git a/autoconf/config.guess b/autoconf/config.guess
index 8d19e07..cc75590 100755
--- a/autoconf/config.guess
+++ b/autoconf/config.guess
@@ -633,6 +633,7 @@
 	  armlinux)   echo "${UNAME_MACHINE}-unknown-linuxaout" ; exit 0 ;;
 	  m68klinux)  echo "${UNAME_MACHINE}-unknown-linuxaout" ; exit 0 ;;
 	  elf32ppc)   echo "powerpc-unknown-linux"              ; exit 0 ;;
+	  elf_s390)   echo "${UNAME_MACHINE}-ibm-linux"         ; exit 0 ;;
 	esac
 
 	if test "${UNAME_MACHINE}" = "alpha" ; then
diff --git a/autoconf/config.sub b/autoconf/config.sub
index e29f273..b64c20d 100755
--- a/autoconf/config.sub
+++ b/autoconf/config.sub
@@ -159,7 +159,7 @@
 		| hppa | hppa1.0 | hppa1.1 | hppa2.0 | hppa2.0n | hppa2.0w \
 		| alpha | alphaev[4-7] | alphaev56 | alphapca5[67] \
 		| we32k | ns16k | clipper | i370 | sh | powerpc | powerpcle \
-		| 1750a | dsp16xx | pdp11 | mips64 | mipsel | mips64el \
+		| 1750a | dsp16xx | pdp11 | s390 | mips64 | mipsel | mips64el \
 		| mips64orion | mips64orionel | mipstx39 | mipstx39el \
 		| sparc | sparclet | sparclite | sparc64 | v850)
 		basic_machine=$basic_machine-unknown
@@ -533,6 +533,10 @@
 	rtpc | rtpc-*)
 		basic_machine=romp-ibm
 		;;
+	s390-*)
+		basic_machine=s390-ibm
+		os=-linux
+		;;
 	sequent)
 		basic_machine=i386-sequent
 		;;