Index: /branches/BNC_2.12/src/PPP/pppClient.cpp
===================================================================
--- /branches/BNC_2.12/src/PPP/pppClient.cpp	(revision 8451)
+++ /branches/BNC_2.12/src/PPP/pppClient.cpp	(revision 8452)
@@ -19,4 +19,5 @@
 #include <iostream>
 #include <iomanip>
+#include <cmath>
 #include <stdlib.h>
 #include <string.h>
Index: /branches/BNC_2.12/src/PPP_SSR_I/pppFilter.cpp
===================================================================
--- /branches/BNC_2.12/src/PPP_SSR_I/pppFilter.cpp	(revision 8451)
+++ /branches/BNC_2.12/src/PPP_SSR_I/pppFilter.cpp	(revision 8452)
@@ -295,7 +295,7 @@
   bancroft(BB, _xcBanc);
 
-  if (isnan(_xcBanc(1)) ||
-      isnan(_xcBanc(2)) ||
-      isnan(_xcBanc(3))) {
+  if (std::isnan(_xcBanc(1)) ||
+      std::isnan(_xcBanc(2)) ||
+      std::isnan(_xcBanc(3))) {
     return failure;
   }