diff --git a/include/kernel.mk b/include/kernel.mk
index 748605705289425a6363d8855557476845253b4c..f9baeef0ac3daa5505344310b9656c49c960931a 100644
--- a/include/kernel.mk
+++ b/include/kernel.mk
@@ -51,13 +51,14 @@ endif
 ifneq (,$(findstring uml,$(BOARD)))
   LINUX_KARCH:=um
 else
-  LINUX_KARCH:=$(shell echo $(ARCH) | sed -e 's/i[3-9]86/i386/' \
-	-e 's/mipsel/mips/' \
-	-e 's/mipseb/mips/' \
-	-e 's/powerpc/ppc/' \
-	-e 's/sh[234]/sh/' \
-	-e 's/armeb/arm/' \
-  )
+  ifeq (,$(LINUX_KARCH))
+    LINUX_KARCH:=$(shell echo $(ARCH) | sed -e 's/i[3-9]86/i386/' \
+	  -e 's/mipsel/mips/' \
+	  -e 's/mipseb/mips/' \
+	  -e 's/sh[234]/sh/' \
+	  -e 's/armeb/arm/' \
+    )
+  endif
 endif
 
 
diff --git a/target/linux/amcc/Makefile b/target/linux/amcc/Makefile
index d582d8191531f6b24d956e7eb1b49f4863558263..5e52d38c77aa1ef2e8e8a6853ce95590863a4615 100644
--- a/target/linux/amcc/Makefile
+++ b/target/linux/amcc/Makefile
@@ -12,6 +12,7 @@ BOARDNAME:=AMCC Taishan
 FEATURES:=jffs2
 
 LINUX_VERSION:=2.6.21.5
+LINUX_KARCH:=ppc
 
 include $(INCLUDE_DIR)/target.mk
 
diff --git a/target/linux/magicbox/Makefile b/target/linux/magicbox/Makefile
index b13009562439d7491ba40f68e72d041205e27b60..15f035a82e25c0a846ed801b1a799d2390cee102 100644
--- a/target/linux/magicbox/Makefile
+++ b/target/linux/magicbox/Makefile
@@ -12,6 +12,7 @@ BOARDNAME:=Magicbox
 FEATURES:=squashfs jffs2
 
 LINUX_VERSION:=2.6.22.4
+LINUX_KARCH:=ppc
 
 include $(INCLUDE_DIR)/target.mk