Index: trunk/BNC/src/pppModel.cpp
===================================================================
--- trunk/BNC/src/pppModel.cpp	(revision 6077)
+++ trunk/BNC/src/pppModel.cpp	(revision 6078)
@@ -201,4 +201,9 @@
 ColumnVector t_tides::displacement(const bncTime& time, const ColumnVector& xyz) {
 
+  if (time.undef()) {
+    ColumnVector dX(3); dX = 0.0;
+    return dX;
+  }
+
   double Mjd = time.mjd() + time.daysec() / 86400.0;