diff --git a/src/php/bin/run_tests.sh b/src/php/bin/run_tests.sh
index cf4cc78a52e..d221e666429 100755
--- a/src/php/bin/run_tests.sh
+++ b/src/php/bin/run_tests.sh
@@ -1,3 +1,4 @@
+#!/bin/sh
 # Loads the local shared library, and runs all of the test cases in tests/
 # against it
 cd $(dirname $0)