diff --git a/src/eitd/eitd.h b/src/eitd/eitd.h
index d4ac2cd02..59fea605d 100644
--- a/src/eitd/eitd.h
+++ b/src/eitd/eitd.h
@@ -65,7 +65,7 @@ typedef SIservice * SIservicePtr;
 
 struct OrderServiceUniqueKeyFirstStartTimeEventUniqueKey
 {
-	bool operator()(const SIeventPtr &p1, const SIeventPtr &p2)
+	bool operator()(const SIeventPtr &p1, const SIeventPtr &p2) const
 	{
 		return
 			(p1->get_channel_id() == p2->get_channel_id()) ?
@@ -77,7 +77,7 @@ struct OrderServiceUniqueKeyFirstStartTimeEventUniqueKey
 
 struct OrderFirstEndTimeServiceIDEventUniqueKey
 {
-	bool operator()(const SIeventPtr &p1, const SIeventPtr &p2)
+	bool operator()(const SIeventPtr &p1, const SIeventPtr &p2) const
 	{
 		return
 			p1->times.begin()->startzeit + (long)p1->times.begin()->dauer == p2->times.begin()->startzeit + (long)p2->times.begin()->dauer ?