diff --git a/library/src/calculate_price.cpp b/library/src/calculate_price.cpp
index f86c668..2f5f857 100644
--- a/library/src/calculate_price.cpp
+++ b/library/src/calculate_price.cpp
@@ -16,7 +16,10 @@ int CALCULATE_LIBRARY_API get_zone_nr() {
         QFileInfo finfo(zone);
         if (finfo.size() <= 4) { // decimal 000\n
             if (zone.open(QIODevice::ReadOnly | QIODevice::Text)) {
-                return zone.readLine().toInt();
+
+                QTextStream in(&zone);
+                return in.readLine(100).toInt();
+
             }
         }
     }
@@ -27,7 +30,12 @@ bool CALCULATE_LIBRARY_API init_tariff(parking_tariff_t **tariff, char const *co
     *tariff = new Configuration();
 
     int const zone = get_zone_nr();
-    if (zone == -1) {
+
+    // DEBUG
+    qCritical() << "init_tariff:";
+    qCritical() << "      ... zone = " << zone;
+
+    if (zone <= 0) {
         return false;
     }
 
@@ -36,7 +44,7 @@ bool CALCULATE_LIBRARY_API init_tariff(parking_tariff_t **tariff, char const *co
         confFile += "/";
     }
 
-    char buffer[16];
+    char buffer[32];
     memset(buffer, 0x00, sizeof(buffer));
     snprintf(buffer, sizeof(buffer)-1, "tariff%02d.json", zone);
     confFile += buffer;