diff --git a/src/proxyface/proxyauth.hxx b/src/proxyface/proxyauth.hxx
index 5c2b503..0b5acb0 100644
--- a/src/proxyface/proxyauth.hxx
+++ b/src/proxyface/proxyauth.hxx
@@ -10,8 +10,10 @@
 
 #include <proxyface/ui_proxyauth.hxx>
 #if QT_VERSION >= 0x050000
+#warning Qt 5
 #include <QtWidgets/QDialog>
 #else
+#warning Qt 4
 #include <QtGui/QDialog>
 #endif