Index: mac/wireless-phyExt.cc
--- mac/wireless-phyExt.cc.orig
+++ mac/wireless-phyExt.cc
@@ -425,7 +425,7 @@ int WirelessPhyExt::discard(Packet *p, double power, c
 void WirelessPhyExt::dump(void) const {
 }
 
-void WirelessPhyExt::log(char * event, char* additional) {
+void WirelessPhyExt::log(const char * event, const char* additional) {
 	if (PHY_DBG)
 		cout<<"L "<<Scheduler::instance().clock()<<" "<<node_->nodeid()<<" "<<"PHY"<<" "<<event<<" "
 				<<additional<<endl;