diff --git a/system/uif2iso/uif2iso.SlackBuild b/system/uif2iso/uif2iso.SlackBuild
index c9acd46aad..0c4b3132cd 100644
--- a/system/uif2iso/uif2iso.SlackBuild
+++ b/system/uif2iso/uif2iso.SlackBuild
@@ -28,10 +28,19 @@
 
 PRGNAM=uif2iso
 VERSION=${VERSION:-0.1.7c}
-ARCH=${ARCH:-i486}
 BUILD=${BUILD:-1}
 TAG=${TAG:-_SBo}
 
+# Automatically determine the architecture we're building on:
+if [ -z "$ARCH" ]; then
+  case "$( uname -m )" in
+    i?86) ARCH=i486 ;;
+    arm*) ARCH=arm ;;
+    # Unless $ARCH is already set, use uname -m for all other archs:
+       *) ARCH=$( uname -m ) ;;
+  esac
+fi
+
 CWD=$(pwd)
 TMP=${TMP:-/tmp/SBo}
 PKG=$TMP/package-$PRGNAM