diff --git a/packaging/deb/DEBIAN/prerm b/packaging/deb/DEBIAN/prerm
index 49531028423142ccc9808b90b772bd97b0b3fc58..65f261db2c6c1ac70b761312af68a5188acea541 100644
--- a/packaging/deb/DEBIAN/prerm
+++ b/packaging/deb/DEBIAN/prerm
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-if [ $1 -eq "abort-upgrade" ]; then
+if [ "$1"x = "abort-upgrade"x ]; then
   exit 0
 fi