minor fix
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index d25da0b..a33ff55 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -876,7 +876,7 @@
if args.http2_badserver_interop:
# launch a HTTP2 server emulator that creates edge cases
lang = str(http2InteropServer)
- spec = server_jobspec(Http2Server(), docker_images.get(lang))
+ spec = server_jobspec(http2InteropServer, docker_images.get(lang))
job = dockerjob.DockerJob(spec)
server_jobs[lang] = job
server_addresses[lang] = ('localhost', _DEFAULT_SERVER_PORT)