diff --git a/ChangeLog b/ChangeLog
index 96cbdde5..92fd9cd8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -25,6 +25,8 @@ NEW 2012-05-12 added dump_header. This is a little program which dumps the
 NEW 2012-04-24 added a first version for negative muon fitting. At the same 
                time substaintial bug fixing has been carried out (mainly the
 	       logx/logy handling).
+FIXED 2012-12-18 fixed a shortcoming of the outdated TLemRunHeader class
+                 (see MUSR-246).
 FIXED 2012-11-19 fixes issue with too many t0's in the msr-file (see
                  MUSR-238).
 FIXED 2012-11-19 the Fourier transform had 1 Bin too much, this is fixed now
diff --git a/src/classes/PRunDataHandler.cpp b/src/classes/PRunDataHandler.cpp
index 0b26992b..fd3213c3 100644
--- a/src/classes/PRunDataHandler.cpp
+++ b/src/classes/PRunDataHandler.cpp
@@ -4463,9 +4463,17 @@ Bool_t PRunDataHandler::WriteRootFile(TString fln)
   header->SetNHist(fData[0].GetNoOfHistos());
   header->SetCuts("none");
   header->SetModerator("none");
-  // feed t0's
-  Double_t *tt0 = new Double_t[fData[0].GetNoOfHistos()];
-  for (UInt_t i=0;  i<fData[0].GetNoOfHistos(); i++) {
+
+  // feed t0's if possible
+  UInt_t NoT0s = fData[0].GetNoOfHistos();
+  if (fData[0].GetNoOfHistos() > NHIST) {
+    cerr << endl << ">> PRunDataHandler::WriteRootFile: **WARNING** found more T0's (" << NoT0s << ") than can be handled (" << NHIST << ").";
+    cerr << endl << ">> Will only write the first " << NHIST << " T0s!!" << endl;
+    NoT0s = NHIST;
+  }
+  Double_t *tt0 = new Double_t[NoT0s];
+
+  for (UInt_t i=0;  i<NoT0s; i++) {
     dataSet = fData[0].GetDataSet(i, false); // i.e. the false means, that i is the index and NOT the histo number
     tt0[i] = dataSet->GetTimeZeroBin()/fAny2ManyInfo->rebin;
   }
@@ -4481,7 +4489,7 @@ Bool_t PRunDataHandler::WriteRootFile(TString fln)
      for (UInt_t i=0; i<fData[0].GetNoOfHistos(); i++) {
        dataSet = fData[0].GetDataSet(i, false); // i.e. the false means, that i is the index and NOT the histo number
        if (dataSet == 0) { // something is really wrong
-         cerr << endl << ">> PRunDataHandler::WriteNexusFile: **ERROR** Couldn't get data set (idx=0" << i << ")";
+         cerr << endl << ">> PRunDataHandler::WriteRootFile: **ERROR** Couldn't get data set (idx=0" << i << ")";
          cerr << endl << ">>   something is really wrong!" << endl;
          return false;
        }
@@ -4703,7 +4711,7 @@ Bool_t PRunDataHandler::WriteNexusFile(TString fln)
         }
         size = dataSet->GetData()->size();
         for (UInt_t j=0; j<size; j++) {
-          data.push_back(dataSet->GetData()->at(j));
+          data.push_back((UInt_t)dataSet->GetData()->at(j));
         }
         nxs->GetEntryIdf1()->GetData()->SetHisto(data, i);
         data.clear();
diff --git a/src/external/TLemRunHeader/TLemRunHeader.cxx b/src/external/TLemRunHeader/TLemRunHeader.cxx
index 4c3d9dbf..3928cc45 100644
--- a/src/external/TLemRunHeader/TLemRunHeader.cxx
+++ b/src/external/TLemRunHeader/TLemRunHeader.cxx
@@ -5,6 +5,9 @@
 //
 // $Id: TLemRunHeader.cxx 3897 2009-05-01 22:06:11Z l_wojek $
 //
+#include <iostream>
+using namespace std;
+
 #include "TLemRunHeader.h"
 
 ClassImp(TLemRunHeader)
@@ -190,10 +193,13 @@ void TLemRunHeader::SetModerator(const Char_t *moderator){
 }
 //----------------------------------------------------------
 void TLemRunHeader::SetTimeZero(const Double_t *value){
+ Int_t noT0s = fNHist;
+ if (noT0s > NHIST)
+   noT0s = NHIST;
  TString str;
  str = "16 t0: ";
- for (Int_t i = 0; i < fNHist; i++){
-  //fTimeZero.push_back(value[i]);
+ for (Int_t i = 0; i < noT0s; i++){
+   //fTimeZero.push_back(value[i]);
   fTimeZero[i] = value[i];
   str   += value[i];
   str   += "   ";