diff --git a/tools/gpg-authcode-sign.sh b/tools/gpg-authcode-sign.sh
index 615e1bac7..1bc71559f 100755
--- a/tools/gpg-authcode-sign.sh
+++ b/tools/gpg-authcode-sign.sh
@@ -184,15 +184,16 @@ if [ ! -f $autogenrc ]; then
 fi
 
 # Define the cleanup routine for osslsigncode
-cleanup() {
-    if [[ -n "$outname" && -f "${outname}.tmp" ]]; then
-        echo "Cleaning up: Removing ${outname}.tmp"
+cleanup()
+{
+    if [ -n "$outname" && -f "${outname}.tmp" ]; then
+        echo >&2 "Cleaning up: Removing ${outname}.tmp"
         rm -f "${outname}.tmp"
     fi
 }
 
-# Trap any error to call the cleanup routine
-trap cleanup ERR SIGINT SIGTERM
+# Trap common signals and exit to run the cleanup
+trap cleanup 0 SIGINT SIGTERM
 
 for v in AUTHENTICODE_SIGNHOST AUTHENTICODE_TOOL AUTHENTICODE_TSURL \
          AUTHENTICODE_KEY AUTHENTICODE_CERTS VERSION_SIGNKEY \
@@ -261,7 +262,7 @@ elif [ "$AUTHENTICODE_KEY" = none ]; then
     echo >&2 "$PGM: Signing disabled; would sign: '$inname'"
     [ "$inname" != "$outname" ] && cp "$inname" "$outname"
 
-elif [[ "$AUTHENTICODE_KEY" =~ \.p12$ || "$AUTHENTICODE_KEY" =~ \.pfx$ ]]; then
+elif [ -n $(echo "$AUTHENTICODE_KEY" | egrep "\.(pfx|p12)$") ]; then
 
     echo >&2 "$PGM: Signing using PKCS#12 container $AUTHENTICODE_KEY"
     osslsigncode sign -certs "$AUTHENTICODE_CERTS" \