diff -r d78fea0f664c -r a0ad72800b96 src/gui.cpp
--- a/src/gui.cpp	Fri Oct 18 22:07:26 2013 +0300
+++ b/src/gui.cpp	Fri Oct 18 22:30:08 2013 +0300
@@ -242,6 +242,12 @@
 			title += '*';
 	}
 
+#ifdef DEBUG
+	title += " [debug build]";
+#elif BUILD_ID != BUILD_RELEASE
+	title += " [release build]";
+#endif // DEBUG
+
 	setWindowTitle (title);
 }