diff --git a/Dockerfile b/Dockerfile
index 4ea2fcf..e51ef1c 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -94,4 +94,4 @@ COPY init /sbin/init
 ENTRYPOINT [ "/sbin/init" ]
 
 # Our ndoes are in ../nodes/node[0-9]
-RUN sed -ie 's#=../node\([0-9]\+\)/#=../nodes/node\1/#' /opt/sbbs/ctrl.orig/main.ini
+RUN sed -i -e 's#=../node\([0-9]\+\)/#=../nodes/node\1/#' /opt/sbbs/ctrl.orig/main.ini