Index: src/MainWindow.hxx
===================================================================
--- src/MainWindow.hxx	(revision 14303)
+++ src/MainWindow.hxx	(working copy)
@@ -45,6 +45,8 @@
 #define DATA_EXAMPLES_PATH "example-data"
 #endif
 
+#include <QtXmlPatterns>
+
 class PlaybackIndicator : public QLabel
 {
 Q_OBJECT
@@ -214,8 +216,85 @@
 		on_action_Save_triggered();
 		return _canvas->isChanged()? abort : goOn;;
 	}
+
+	void versionTokenizer(std::vector<int>& numbers, std::string version)
+	{
+		int firstDot = version.find(".");
+		numbers.push_back( atoi(version.substr(0, firstDot).c_str()) );
+	
+		int secondDot = version.find(".", firstDot + 1);
+		numbers.push_back( atoi(version.substr(firstDot + 1, secondDot - firstDot - 1).c_str()) );
+
+		int lastDot = version.find(".", secondDot + 1);
+		numbers.push_back( atoi(version.substr(secondDot + 1, lastDot - secondDot - 1).c_str()) );
+	}
+
 	void load(const QString & filename)
 	{
+		QXmlQuery query;
+		QFile file(filename);
+		if( !file.exists() )
+		{
+			QMessageBox::critical(this, tr("Error loading the network"), 
+					tr("<p>The file you selected doesn't exist.<p>"));
+			return;
+		}
+		std::string currentVersion = CLAM::GetVersion();
+
+		file.open(QIODevice::ReadOnly);
+		query.bindVariable("document", &file);
+		query.setQuery("doc($document)/network/@clamVersion/string()");	
+
+		QString readClamVersion;
+		query.evaluateTo(&readClamVersion);
+		readClamVersion = readClamVersion.trimmed();
+
+		std::vector<int> numbersCurrentVersion;
+		versionTokenizer(numbersCurrentVersion, currentVersion);
+
+		std::vector<int> numbersFileVersion;
+		versionTokenizer(numbersFileVersion, qPrintable(readClamVersion) );
+
+		bool outdated = false;
+		for(unsigned int i = 0; i < numbersFileVersion.size(); i++)
+		{		
+			if( numbersCurrentVersion[i] > numbersFileVersion[i] )
+			{
+				outdated = true;
+				break;
+			}
+			if( numbersCurrentVersion[i] < numbersFileVersion[i] )
+			{
+				QMessageBox::warning(this, tr("NetworkEditor update."),
+						tr("This network was created with a newer version of NetworkEditor.\n"
+						"Maybe you should update."),
+						QMessageBox::Ok, QMessageBox::Ok);
+				loadVersionChecked(filename);
+				return;
+			}
+		}
+		if( !outdated )
+		{	
+			loadVersionChecked(filename);
+			return;
+		}		
+		int option =  QMessageBox::warning(this, tr("This file was created with an old version of NetworkEditor."),
+						tr("Do you want to convert to current version?\n"
+						"NetworkEditor won't open the file if you don't convert it"),
+						QMessageBox::No | QMessageBox::Yes, QMessageBox::Yes);
+		switch (option)
+		{
+			case QMessageBox::Yes:
+			std::cout << "Converting to " << currentVersion << "..." << std::endl;
+			// Call the python script and convert to current
+			loadVersionChecked(filename);
+			return;
+			case QMessageBox::No:
+			return; // We don't allow the network to be loaded
+		}
+	}
+	void loadVersionChecked(const QString & filename)
+	{
 		_network.ResetConnectionReport();
 
 		std::string localFilename = filename.toLocal8Bit().constData();
Index: SConstruct
===================================================================
--- SConstruct	(revision 14303)
+++ SConstruct	(working copy)
@@ -79,6 +79,7 @@
 	'QtUiTools',
 	'QtDesigner',
 	'QtWebKit',
+	'QtXmlPatterns',
 	],
 	debug=False,
 	crosscompiling=crosscompiling,