diff --git a/libretroshare/src/rsserver/p3peers.cc b/libretroshare/src/rsserver/p3peers.cc
index d6d6f9f03..73a5801fd 100644
--- a/libretroshare/src/rsserver/p3peers.cc
+++ b/libretroshare/src/rsserver/p3peers.cc
@@ -901,6 +901,12 @@ bool 	p3Peers::setLocalAddress(const RsPeerId &id, const std::string &addr_str,
         std::cerr << "p3Peers::setLocalAddress() " << id << std::endl;
 #endif
 
+        if(port < 1024)
+        {
+            std::cerr << "(EE) attempt to use a port that is reserved to the system: " << port << std::endl;
+            return false ;
+        }
+
 	struct sockaddr_storage addr;
 	struct sockaddr_in *addrv4p = (struct sockaddr_in *) &addr;
 	addrv4p->sin_family = AF_INET;
@@ -926,6 +932,12 @@ bool 	p3Peers::setExtAddress(const RsPeerId &id, const std::string &addr_str, ui
 #ifdef P3PEERS_DEBUG
         std::cerr << "p3Peers::setExtAddress() " << id << std::endl;
 #endif
+        if(port < 1024)
+        {
+            std::cerr << "(EE) attempt to use a port that is reserved to the system: " << port << std::endl;
+            return false ;
+        }
+
 
 	// NOTE THIS IS IPV4 FOR NOW.
 	struct sockaddr_storage addr;