diff --git a/src/com/intelligt/modbus/jlibmodbus/Modbus.java b/src/com/intelligt/modbus/jlibmodbus/Modbus.java
index b9ef374..194c465 100644
--- a/src/com/intelligt/modbus/jlibmodbus/Modbus.java
+++ b/src/com/intelligt/modbus/jlibmodbus/Modbus.java
@@ -290,7 +290,7 @@ static public boolean checkEndAddress(int value) {
      * @return "true" if register value is correct, else "false".
      */
     static public boolean checkRegisterValue(int value) {
-        return checkRange(value, 0, Modbus.MAX_REGISTER_VALUE);
+        return checkRange((short)value, 0, Modbus.MAX_REGISTER_VALUE);
     }
 
     /**
diff --git a/src/com/intelligt/modbus/jlibmodbus/data/ModbusHoldingRegisters.java b/src/com/intelligt/modbus/jlibmodbus/data/ModbusHoldingRegisters.java
index 9fc5507..f3c3e7e 100644
--- a/src/com/intelligt/modbus/jlibmodbus/data/ModbusHoldingRegisters.java
+++ b/src/com/intelligt/modbus/jlibmodbus/data/ModbusHoldingRegisters.java
@@ -188,7 +188,7 @@ private void checkRange(int offset, int quantity) throws IllegalDataAddressExcep
     }
 
     private void checkAddress(int offset) throws IllegalDataAddressException {
-        if (offset > (getQuantity() - 1))
+        if (DataUtils.wordLow(offset) > (getQuantity() - 1))
             throw new IllegalDataAddressException(offset);
     }