diff --git a/application/windows/MainWindow.cpp b/application/windows/MainWindow.cpp
index 7f63a63..8eab286 100644
--- a/application/windows/MainWindow.cpp
+++ b/application/windows/MainWindow.cpp
@@ -149,9 +149,11 @@ MainWindow::MessageReceived(BMessage* message)
 			invite->AddInt32("im_what", IM_ROOM_SEND_INVITE);
 			invite->AddString("chat_id", chat_id);
 
-			BLooper* looper = (BLooper*)fConversation->GetProtocolLooper();
+			ProtocolLooper* plooper = fConversation->GetProtocolLooper();
+			BLooper* looper = (BLooper*)plooper;
 			fRosterWindow = new RosterWindow("Invite contact to chat"
-				B_UTF8_ELLIPSIS, invite, new BMessenger(looper), fServer);
+				B_UTF8_ELLIPSIS, invite, new BMessenger(looper), fServer,
+				plooper->GetInstance());
 
 			fRosterWindow->Show();
 			break;
diff --git a/application/windows/RosterWindow.cpp b/application/windows/RosterWindow.cpp
index 0b25646..39dd8f1 100644
--- a/application/windows/RosterWindow.cpp
+++ b/application/windows/RosterWindow.cpp
@@ -45,9 +45,28 @@ RosterWindow::RosterWindow(const char* title, BMessage* selectMsg,
 	fRosterView->SetInvocationMessage(new BMessage(kSendMessage));
 
 	fOkButton = new BButton("OK", new BMessage(kSendMessage));
-	fAccountField = new BMenuField("accountMenuField", NULL,
-		CreateAccountMenu(fAccounts, BMessage(kSelAccount),
-			new BMessage(kSelNoAccount)));
+
+	BMenu* accountMenu;
+
+	// If a specific instance is given, disallow selecting other accounts
+	if (instance > -1) {
+		accountMenu = new BMenu("accountMenu");
+		BString name = "N/A";
+		for (int i = 0; i < fAccounts.CountItems(); i++)
+			if (fAccounts.ValueAt(i) == instance) {
+				name = fAccounts.KeyAt(i);
+				break;
+			}
+		accountMenu->AddItem(new BMenuItem(name.String(), NULL));
+		accountMenu->SetLabelFromMarked(true);
+		accountMenu->ItemAt(0)->SetMarked(true);
+		accountMenu->SetEnabled(false);
+	}
+	else
+		accountMenu = CreateAccountMenu(fAccounts, BMessage(kSelAccount),
+			new BMessage(kSelNoAccount));
+
+	fAccountField = new BMenuField("accountMenuField", NULL, accountMenu);
 
 	BLayoutBuilder::Group<>(this, B_VERTICAL, 0.0f)
 		.SetInsets(B_USE_DEFAULT_SPACING)