diff --git a/camlibs/ptp2/ptp.c b/camlibs/ptp2/ptp.c
index cb01ae3ed..445e74a5c 100644
--- a/camlibs/ptp2/ptp.c
+++ b/camlibs/ptp2/ptp.c
@@ -2134,6 +2134,24 @@ store_event:
 	if (ret == PTP_RC_OK) {
 		ptp_debug (params, "event: nparams=0x%X, code=0x%X, trans_id=0x%X, p1=0x%X, p2=0x%X, p3=0x%X", event.Nparam,event.Code,event.Transaction_ID, event.Param1, event.Param2, event.Param3);
 		ptp_add_event (params, &event);
+
+		/* handle some PTP stack internal events */
+		switch (event.Code) {
+		case PTP_EC_DevicePropChanged: {
+			unsigned int i;
+
+			/* mark the property for a forced refresh on the next query */
+			for (i=0;i<params->nrofdeviceproperties;i++)
+				if (params->deviceproperties[i].desc.DevicePropertyCode == event.Param1) {
+					params->deviceproperties[i].timestamp = 0;
+					break;
+				}
+			break;
+		}
+		default: /* check if we should handle it internally too */
+			break;
+		}
+	
 	}
 	if (ret == PTP_ERROR_TIMEOUT) /* ok, just new events */
 		ret = PTP_RC_OK;