diff --git a/net/acme/Makefile b/net/acme/Makefile
index 5f0dc0f84..7bf98cc06 100644
--- a/net/acme/Makefile
+++ b/net/acme/Makefile
@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=acme
 PKG_VERSION:=2.7.9
-PKG_RELEASE:=3
+PKG_RELEASE:=4
 PKG_LICENSE:=GPLv3
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
diff --git a/net/acme/files/run.sh b/net/acme/files/run.sh
index a0a9a784c..233abee68 100644
--- a/net/acme/files/run.sh
+++ b/net/acme/files/run.sh
@@ -99,7 +99,7 @@ pre_checks()
                         return 1
                     fi
                     debug "Waiting for nginx to stop..."
-                    tries=$tries+1
+                    tries=$((tries + 1))
                     sleep 1
                 done
             ;;