diff --git a/arduino-core/src/processing/app/PreferencesData.java b/arduino-core/src/processing/app/PreferencesData.java
index 41f3cf6c0..a273221a3 100644
--- a/arduino-core/src/processing/app/PreferencesData.java
+++ b/arduino-core/src/processing/app/PreferencesData.java
@@ -146,6 +146,11 @@ public class PreferencesData {
     return (value == null) ? defaultValue : value;
   }
 
+  static public String getNonEmpty(String attribute, String defaultValue) {
+    String value = get(attribute, defaultValue);
+    return ("".equals(value)) ? defaultValue : value;
+  }
+
   public static boolean has(String key) {
     return prefs.containsKey(key);
   }
diff --git a/arduino-core/src/processing/app/Serial.java b/arduino-core/src/processing/app/Serial.java
index f3988f867..c411d2594 100644
--- a/arduino-core/src/processing/app/Serial.java
+++ b/arduino-core/src/processing/app/Serial.java
@@ -50,27 +50,27 @@ public class Serial implements SerialPortEventListener {
   public Serial() throws SerialException {
     this(PreferencesData.get("serial.port"),
       PreferencesData.getInteger("serial.debug_rate", 9600),
-      PreferencesData.get("serial.parity", "N").charAt(0),
+      PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1));
   }
 
   public Serial(int irate) throws SerialException {
     this(PreferencesData.get("serial.port"), irate,
-      PreferencesData.get("serial.parity", "N").charAt(0),
+      PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1));
   }
 
   public Serial(String iname, int irate) throws SerialException {
-    this(iname, irate, PreferencesData.get("serial.parity", "N").charAt(0),
+    this(iname, irate, PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1));
   }
 
   public Serial(String iname) throws SerialException {
     this(iname, PreferencesData.getInteger("serial.debug_rate", 9600),
-      PreferencesData.get("serial.parity", "N").charAt(0),
+      PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1));
   }