diff --git a/config.sub b/config.sub
index 1145e2c9ce..0223922fc9 100755
--- a/config.sub
+++ b/config.sub
@@ -127,6 +127,9 @@ case $os in
 	-windowsnt*)
 		os=`echo $os | sed -e 's/windowsnt/winnt/'`
 		;;
+	-psos*)
+		os=-psos
+		;;
 esac
 
 # Decode aliases for certain CPU-COMPANY combinations.
@@ -654,7 +657,7 @@ case $os in
 	      | -lynxos* | -bosx* | -nextstep* | -cxux* | -aout* | -elf* \
 	      | -ptx* | -coff* | -ecoff* | -winnt* | -domain* | -vsta* \
 	      | -udi* | -eabi* | -lites* | -ieee* | -go32* | -aux* \
-	      | -cygwin32* | -pe*)
+	      | -cygwin32* | -pe* -psos*)
 	# Remember, each alternative MUST END IN *, to match a version number.
 		;;
 	-sunos5*)