diff --git a/dlls/dpnet/client.c b/dlls/dpnet/client.c
index f6f9e79136e..36df50de247 100644
--- a/dlls/dpnet/client.c
+++ b/dlls/dpnet/client.c
@@ -40,6 +40,10 @@ typedef struct IDirectPlay8LobbyClientImpl
 {
     IDirectPlay8LobbyClient IDirectPlay8LobbyClient_iface;
     LONG ref;
+
+    PFNDPNMESSAGEHANDLER msghandler;
+    DWORD flags;
+    void *usercontext;
 } IDirectPlay8LobbyClientImpl;
 
 static inline IDirectPlay8LobbyClientImpl *impl_from_IDirectPlay8LobbyClient(IDirectPlay8LobbyClient *iface)
@@ -427,9 +431,16 @@ static HRESULT WINAPI lobbyclient_Initialize(IDirectPlay8LobbyClient *iface, voi
 {
     IDirectPlay8LobbyClientImpl *This = impl_from_IDirectPlay8LobbyClient(iface);
 
-    FIXME("(%p)->(%p %p 0x%08x)\n", This, context, msghandler, flags);
+    TRACE("(%p):(%p,%p,%x)\n", This, context, msghandler, flags);
 
-    return E_NOTIMPL;
+    if(!msghandler)
+        return E_POINTER;
+
+    This->usercontext = context;
+    This->msghandler = msghandler;
+    This->flags = flags;
+
+    return DPN_OK;
 }
 
 static HRESULT WINAPI lobbyclient_EnumLocalPrograms(IDirectPlay8LobbyClient *iface, GUID* guidapplication,
diff --git a/dlls/dpnet/tests/client.c b/dlls/dpnet/tests/client.c
index f7d6c53b511..673203499bd 100644
--- a/dlls/dpnet/tests/client.c
+++ b/dlls/dpnet/tests/client.c
@@ -220,8 +220,11 @@ static void test_lobbyclient(void)
     ok(hr == S_OK, "Failed to create object\n");
     if(SUCCEEDED(hr))
     {
+        hr = IDirectPlay8LobbyClient_Initialize(client, NULL, NULL, 0);
+        ok(hr == E_POINTER, "got 0x%08x\n", hr);
+
         hr = IDirectPlay8LobbyClient_Initialize(client, NULL, DirectPlayLobbyClientMessageHandler, 0);
-        todo_wine ok(hr == S_OK, "got 0x%08x\n", hr);
+        ok(hr == S_OK, "got 0x%08x\n", hr);
 
         hr = IDirectPlay8LobbyClient_Close(client, 0);
         todo_wine ok(hr == S_OK, "got 0x%08x\n", hr);