diff --git a/tests/test_test.py b/tests/test_test.py
index <HASH>..<HASH> 100644
--- a/tests/test_test.py
+++ b/tests/test_test.py
@@ -403,4 +403,4 @@ def test_multiple_cookies():
     resp = client.get('/')
     assert resp.data == '[]'
     resp = client.get('/')
-    assert resp.data == "[('test1', u'foo,'), ('test2', u'bar')]"
+    assert resp.data == "[('test1', u'foo'), ('test2', u'bar')]"
diff --git a/werkzeug/test.py b/werkzeug/test.py
index <HASH>..<HASH> 100644
--- a/werkzeug/test.py
+++ b/werkzeug/test.py
@@ -152,7 +152,7 @@ class _TestCookieJar(CookieJar):
         for cookie in self:
             cvals.append('%s=%s' % (cookie.name, cookie.value))
         if cvals:
-            environ['HTTP_COOKIE'] = ', '.join(cvals)
+            environ['HTTP_COOKIE'] = '; '.join(cvals)
 
     def extract_wsgi(self, environ, headers):
         """Extract the server's set-cookie headers as cookies into the
Fixed a typo that broke a test and multiple cookies in test client