diff --git a/WebWidgets/src/ComboBoxCell.cpp b/WebWidgets/src/ComboBoxCell.cpp
index d3dadbb53..128ddb1c4 100644
--- a/WebWidgets/src/ComboBoxCell.cpp
+++ b/WebWidgets/src/ComboBoxCell.cpp
@@ -146,6 +146,8 @@ bool ComboBoxCell::serializeJSON(std::ostream& out, const std::string& name)
 		else
 			out << getFormatter()->format(sel);
 	}
+	else 
+		out << "''";
 	return true;	
 }
 
diff --git a/WebWidgets/src/DateFieldCell.cpp b/WebWidgets/src/DateFieldCell.cpp
index 298c9f55a..a86366bf8 100644
--- a/WebWidgets/src/DateFieldCell.cpp
+++ b/WebWidgets/src/DateFieldCell.cpp
@@ -70,6 +70,8 @@ bool DateFieldCell::serializeJSON(std::ostream& out, const std::string& name)
 	{
 		out << "'" << getFormatter()->format(getValue()) << "'";
 	}
+	else 
+		out << "''";
 	return true;
 }
 
diff --git a/WebWidgets/src/ListBoxCell.cpp b/WebWidgets/src/ListBoxCell.cpp
index 5405236a3..d821183ea 100644
--- a/WebWidgets/src/ListBoxCell.cpp
+++ b/WebWidgets/src/ListBoxCell.cpp
@@ -171,7 +171,7 @@ const Any& ListBoxCell::getSelected() const
 
 bool ListBoxCell::serializeJSON(std::ostream& out, const std::string& name)
 {
-	out << name;
+	out << name << ":";
 	if (hasSelected())
 	{
 		const Poco::Any& sel = getSelected();
@@ -180,6 +180,8 @@ bool ListBoxCell::serializeJSON(std::ostream& out, const std::string& name)
 		else
 			out << ":" << getFormatter()->format(sel);
 	}
+	else 
+		out << "''";
 	return true;
 }
 
diff --git a/WebWidgets/src/NumberFieldCell.cpp b/WebWidgets/src/NumberFieldCell.cpp
index 8675d20c5..30aa89962 100644
--- a/WebWidgets/src/NumberFieldCell.cpp
+++ b/WebWidgets/src/NumberFieldCell.cpp
@@ -61,6 +61,8 @@ bool NumberFieldCell::serializeJSON(std::ostream& out, const std::string& name)
 	{
 		out << getFormatter()->format(getValue());
 	}
+	else 
+		out << "''";
 	return true;
 }
 
diff --git a/WebWidgets/src/PasswordFieldCell.cpp b/WebWidgets/src/PasswordFieldCell.cpp
index 215708f1d..a703d84d2 100644
--- a/WebWidgets/src/PasswordFieldCell.cpp
+++ b/WebWidgets/src/PasswordFieldCell.cpp
@@ -59,6 +59,8 @@ bool PasswordFieldCell::serializeJSON(std::ostream& out, const std::string& name
 	{
 		out << "'" << getFormatter()->format(getValue()) << "'";
 	}
+	else 
+		out << "''";
 	return true;
 }
 
diff --git a/WebWidgets/src/TextEditCell.cpp b/WebWidgets/src/TextEditCell.cpp
index 60ec8a2bc..f8db44a4f 100644
--- a/WebWidgets/src/TextEditCell.cpp
+++ b/WebWidgets/src/TextEditCell.cpp
@@ -80,6 +80,8 @@ bool TextEditCell::serializeJSON(std::ostream& out, const std::string& name)
 	{
 		out << "'" << getFormatter()->format(getValue()) << "'";
 	}
+	else 
+		out << "''";
 	return true;
 }
 
diff --git a/WebWidgets/src/TextFieldCell.cpp b/WebWidgets/src/TextFieldCell.cpp
index a520ddd62..eae2da0ab 100644
--- a/WebWidgets/src/TextFieldCell.cpp
+++ b/WebWidgets/src/TextFieldCell.cpp
@@ -99,6 +99,8 @@ bool TextFieldCell::serializeJSON(std::ostream& out, const std::string& name)
 	{
 		out << "'" << getFormatter()->format(getValue()) << "'";
 	}
+	else 
+		out << "''";
 	return true;
 }
 
diff --git a/WebWidgets/src/TimeFieldCell.cpp b/WebWidgets/src/TimeFieldCell.cpp
index 49611d75e..99b07e2c7 100644
--- a/WebWidgets/src/TimeFieldCell.cpp
+++ b/WebWidgets/src/TimeFieldCell.cpp
@@ -85,6 +85,8 @@ bool TimeFieldCell::serializeJSON(std::ostream& out, const std::string& name)
 	{
 		out << "'" << getFormatter()->format(getValue()) << "'";
 	}
+	else 
+		out << "''";
 	return true;
 }