Index: /trunk/FACT++/src/dataLogger.cc
===================================================================
--- /trunk/FACT++/src/dataLogger.cc	(revision 10818)
+++ /trunk/FACT++/src/dataLogger.cc	(revision 10819)
@@ -2029,5 +2029,5 @@
     const Converter::FormatList flist = sub.fConv->GetList();
     // Compilation failed
-    if (flist.empty() || flist.back().first.second!=0)
+    if (!sub.fConv->valid())
     {
         Error("Compilation of format string failed.");