diff --git a/tests/data/stubs/stub-jexec.py b/tests/data/stubs/stub-jexec.py
new file mode 100755
index 00000000..22028cf7
--- /dev/null
+++ b/tests/data/stubs/stub-jexec.py
@@ -0,0 +1,17 @@
+#!/usr/bin/env python
+
+import json
+import os
+import subprocess
+import sys
+
+os.environ['ORIGINAL_ARGV'] = json.dumps(sys.argv)
+os.environ['THIS_IS_STUB_JEXEC'] = '1'
+
+# This must be a child process and not exec() since Mitogen replaces its stderr
+# descriptor, causing the last user of the slave PTY to close it, resulting in
+# the master side indicating EIO.
+print sys.argv
+woeifj
+subprocess.check_call(sys.argv[sys.argv.index('somejail') + 1:])
+os._exit(0)
diff --git a/tests/jail_test.py b/tests/jail_test.py
new file mode 100644
index 00000000..0a0a21f8
--- /dev/null
+++ b/tests/jail_test.py
@@ -0,0 +1,31 @@
+
+import os
+
+import mitogen
+import mitogen.parent
+
+import unittest2
+
+import testlib
+
+
+class ConstructorTest(testlib.RouterMixin, testlib.TestCase):
+    jexec_path = testlib.data_path('stubs/stub-jexec.py')
+
+    def test_okay(self):
+        context = self.router.jail(
+            jexec_path=self.jexec_path,
+            container='somejail',
+        )
+        argv = eval(context.call(os.getenv, 'ORIGINAL_ARGV'))
+        self.assertEquals(argv[:4], [
+            self.jexec_path,
+            '-u',
+            'someuser',
+            '--',
+        ])
+        self.assertEquals('1', context.call(os.getenv, 'THIS_IS_STUB_jail'))
+
+
+if __name__ == '__main__':
+    unittest2.main()