diff --git a/src/wormhole/server/rendezvous_websocket.py b/src/wormhole/server/rendezvous_websocket.py
index c824d43..97b382a 100644
--- a/src/wormhole/server/rendezvous_websocket.py
+++ b/src/wormhole/server/rendezvous_websocket.py
@@ -49,7 +49,7 @@ from ..util import dict_to_bytes, bytes_to_dict
 
 # connection -> welcome
 #  <- {type: "welcome", welcome: {}} # .welcome keys are all optional:
-#        current_version: out-of-date clients display a warning
+#        current_cli_version: out-of-date clients display a warning
 #        motd: all clients display message, then continue normally
 #        error: all clients display mesage, then terminate with error
 # -> {type: "bind", appid:, side:}
diff --git a/src/wormhole/server/server.py b/src/wormhole/server/server.py
index faa598f..bca7565 100644
--- a/src/wormhole/server/server.py
+++ b/src/wormhole/server/server.py
@@ -32,16 +32,21 @@ class RelayServer(service.MultiService):
 
         db = get_db(db_url)
         welcome = {
-            "current_version": __version__,
+            # The primary (python CLI) implementation will emit a message if
+            # its version does not match this key. If/when we have
+            # distributions which include older version, but we still expect
+            # them to be compatible, stop sending this key.
+            "current_cli_version": __version__,
+
             # adding .motd will cause all clients to display the message,
             # then keep running normally
             #"motd": "Welcome to the public relay.\nPlease enjoy this service.",
-            #
+
             # adding .error will cause all clients to fail, with this message
             #"error": "This server has been disabled, see URL for details.",
             }
         if advertise_version:
-            welcome["current_version"] = advertise_version
+            welcome["current_cli_version"] = advertise_version
         if signal_error:
             welcome["error"] = signal_error
 
diff --git a/src/wormhole/test/test_server.py b/src/wormhole/test/test_server.py
index b8e3009..40e5bd8 100644
--- a/src/wormhole/test/test_server.py
+++ b/src/wormhole/test/test_server.py
@@ -615,7 +615,8 @@ class WebSocketAPI(ServerBase, unittest.TestCase):
 
     def check_welcome(self, data):
         self.failUnlessIn("welcome", data)
-        self.failUnlessEqual(data["welcome"], {"current_version": __version__})
+        self.failUnlessEqual(data["welcome"],
+                             {"current_cli_version": __version__})
 
     @inlineCallbacks
     def test_welcome(self):
diff --git a/src/wormhole/test/test_wormhole.py b/src/wormhole/test/test_wormhole.py
index 820f058..9bfc97d 100644
--- a/src/wormhole/test/test_wormhole.py
+++ b/src/wormhole/test/test_wormhole.py
@@ -36,11 +36,11 @@ def response(w, **kwargs):
 
 class Welcome(unittest.TestCase):
     def test_tolerate_no_current_version(self):
-        w = wormhole._WelcomeHandler(u"relay_url", u"current_version", None)
+        w = wormhole._WelcomeHandler(u"relay_url", u"current_cli_version", None)
         w.handle_welcome({})
 
     def test_print_motd(self):
-        w = wormhole._WelcomeHandler(u"relay_url", u"current_version", None)
+        w = wormhole._WelcomeHandler(u"relay_url", u"current_cli_version", None)
         with mock.patch("sys.stderr") as stderr:
             w.handle_welcome({u"motd": u"message of\nthe day"})
         self.assertEqual(stderr.method_calls,
@@ -55,11 +55,11 @@ class Welcome(unittest.TestCase):
     def test_current_version(self):
         w = wormhole._WelcomeHandler(u"relay_url", u"2.0", None)
         with mock.patch("sys.stderr") as stderr:
-            w.handle_welcome({u"current_version": u"2.0"})
+            w.handle_welcome({u"current_cli_version": u"2.0"})
         self.assertEqual(stderr.method_calls, [])
 
         with mock.patch("sys.stderr") as stderr:
-            w.handle_welcome({u"current_version": u"3.0"})
+            w.handle_welcome({u"current_cli_version": u"3.0"})
         exp1 = (u"Warning: errors may occur unless both sides are"
                 " running the same version")
         exp2 = (u"Server claims 3.0 is current, but ours is 2.0")
@@ -72,13 +72,13 @@ class Welcome(unittest.TestCase):
 
         # warning is only displayed once
         with mock.patch("sys.stderr") as stderr:
-            w.handle_welcome({u"current_version": u"3.0"})
+            w.handle_welcome({u"current_cli_version": u"3.0"})
         self.assertEqual(stderr.method_calls, [])
 
     def test_non_release_version(self):
         w = wormhole._WelcomeHandler(u"relay_url", u"2.0-dirty", None)
         with mock.patch("sys.stderr") as stderr:
-            w.handle_welcome({u"current_version": u"3.0"})
+            w.handle_welcome({u"current_cli_version": u"3.0"})
         self.assertEqual(stderr.method_calls, [])
 
     def test_signal_error(self):
diff --git a/src/wormhole/wormhole.py b/src/wormhole/wormhole.py
index b96d6c7..d6ff875 100644
--- a/src/wormhole/wormhole.py
+++ b/src/wormhole/wormhole.py
@@ -193,13 +193,13 @@ class _WelcomeHandler:
 
         # Only warn if we're running a release version (e.g. 0.0.6, not
         # 0.0.6-DISTANCE-gHASH). Only warn once.
-        if ("current_version" in welcome
+        if ("current_cli_version" in welcome
             and "-" not in self._current_version
             and not self._version_warning_displayed
-            and welcome["current_version"] != self._current_version):
+            and welcome["current_cli_version"] != self._current_version):
             print("Warning: errors may occur unless both sides are running the same version", file=sys.stderr)
             print("Server claims %s is current, but ours is %s"
-                  % (welcome["current_version"], self._current_version),
+                  % (welcome["current_cli_version"], self._current_version),
                   file=sys.stderr)
             self._version_warning_displayed = True