diff --git a/apps/py_sems/PySems.cpp b/apps/py_sems/PySems.cpp
index 1cc06046..ae7672c4 100644
--- a/apps/py_sems/PySems.cpp
+++ b/apps/py_sems/PySems.cpp
@@ -36,16 +36,17 @@
 #include <sip.h>
 #include "sip/sipAPIpy_sems_lib.h"
 
+// earlier than 4.7.6, include headers:
 #if SIP_VERSION < 0x040706
-#define SIP_USE_OLD_CLASS_CONVERSION 1
-#endif
-
-#ifdef SIP_USE_OLD_CLASS_CONVERSION
 #include "sip/sippy_sems_libPySemsDialog.h"
 #include "sip/sippy_sems_libPySemsB2BDialog.h"
 #include "sip/sippy_sems_libPySemsB2ABDialog.h"
 #endif
 
+#if SIP_VERSION < 0x040901
+#define SIP_USE_OLD_CLASS_CONVERSION 1
+#endif
+
 #include <unistd.h>
 #include <pthread.h>
 #include <regex.h>