--- a/gui/octave-gui.pro
+++ b/gui/octave-gui.pro
@@ -86,7 +86,9 @@
     src/SettingsDialog.cpp \
     src/OctaveGUI.cpp \
     src/ResourceManager.cpp \
-    src/CommandLineParser.cpp
+    src/CommandLineParser.cpp \
+    src/OctaveMainThread.cpp \
+    src/OctaveCallbackThread.cpp
 
 HEADERS += \
         src/terminal/TerminalCharacterDecoder.h \
@@ -130,7 +132,9 @@
     src/qirc/IClientSocket.h \
     src/SettingsDialog.h \
     src/ResourceManager.h \
-    src/CommandLineParser.h
+    src/CommandLineParser.h \
+    src/OctaveMainThread.h \
+    src/OctaveCallbackThread.h
 
 FORMS += \
     src/SettingsDialog.ui

--- a/gui/src/MainWindow.cpp
+++ b/gui/src/MainWindow.cpp
@@ -26,6 +26,7 @@
 #include "FileEditorMdiSubWindow.h"
 #include "ImageViewerMdiSubWindow.h"
 #include "SettingsDialog.h"
+#include "OctaveCallbackThread.h"
 #include "cmd-edit.h"
 
 #define VERSION_STRING "Octave GUI (0.6.0)"

--- a/gui/src/MainWindow.h
+++ b/gui/src/MainWindow.h
@@ -35,8 +35,8 @@
 #include "BrowserWidget.h"
 #include "IRCWidget.h"
 
-class OctaveMainThread;
 class OctaveCallbackThread;
+#include "OctaveMainThread.h"
 
 /**
   * \class MainWindow
@@ -120,60 +120,4 @@
   bool m_isRunning;
 };
 
-class OctaveMainThread:public QThread
-{
-Q_OBJECT
-public:
-  OctaveMainThread (QObject * parent):QThread (parent)
-  {
-  }
-
-signals:
-  void ready();
-
-protected:
-  void run ()
-  {
-    int argc = 3;
-    const char *argv[] = { "octave", "--interactive", "--line-editing" };
-    octave_main (argc, (char **) argv, 1);
-    emit ready();
-    main_loop ();
-    clean_up_and_exit (0);
-  }
-};
-
-class OctaveCallbackThread:public QThread
-{
-Q_OBJECT public:
-  OctaveCallbackThread (QObject * parent,
-			MainWindow * mainWindow):QThread (parent),
-    m_mainWindow (mainWindow)
-  {
-  }
-
-protected:
-  void run ()
-  {
-    while (m_mainWindow->isRunning ())
-      {
-        OctaveLink::instance ()->fetchSymbolTable ();
-
-	// Get a full variable list.
-	QList < SymbolRecord > symbolTable =
-          OctaveLink::instance ()->copyCurrentSymbolTable ();
-	if (symbolTable.size ())
-	  {
-	    m_mainWindow->variablesDockWidget ()->
-	      setVariablesList (symbolTable);
-	  }
-
-        OctaveLink::instance ()->updateHistoryModel ();
-        usleep (500000);
-      }
-  }
-private:
-  MainWindow * m_mainWindow;
-};
-
 #endif // MAINWINDOW_H

new file mode 100644
--- /dev/null
+++ b/gui/src/OctaveCallbackThread.cpp
@@ -0,0 +1,26 @@
+#include "OctaveCallbackThread.h"
+
+OctaveCallbackThread::OctaveCallbackThread (QObject * parent,
+                      MainWindow * mainWindow):QThread (parent),
+  m_mainWindow (mainWindow)
+{
+}
+
+void
+OctaveCallbackThread::run ()
+{
+  while (m_mainWindow->isRunning ())
+    {
+      OctaveLink::instance ()->fetchSymbolTable ();
+
+      // Get a full variable list.
+      QList < SymbolRecord > symbolTable = OctaveLink::instance ()->copyCurrentSymbolTable ();
+      if (symbolTable.size ())
+        {
+          m_mainWindow->variablesDockWidget ()->setVariablesList (symbolTable);
+        }
+
+      OctaveLink::instance ()->updateHistoryModel ();
+      usleep (500000);
+    }
+}

new file mode 100644
--- /dev/null
+++ b/gui/src/OctaveCallbackThread.h
@@ -0,0 +1,19 @@
+#ifndef OCTAVECALLBACKTHREAD_H
+#define OCTAVECALLBACKTHREAD_H
+
+#include <QThread>
+#include "MainWindow.h"
+
+class OctaveCallbackThread:public QThread
+{
+  Q_OBJECT
+public:
+  OctaveCallbackThread (QObject * parent, MainWindow * mainWindow);
+
+protected:
+  void run ();
+private:
+  MainWindow * m_mainWindow;
+};
+
+#endif // OCTAVECALLBACKTHREAD_H

new file mode 100644
--- /dev/null
+++ b/gui/src/OctaveMainThread.cpp
@@ -0,0 +1,16 @@
+#include "OctaveMainThread.h"
+
+OctaveMainThread::OctaveMainThread (QObject * parent):QThread (parent)
+{
+}
+
+void
+OctaveMainThread::run ()
+{
+  int argc = 3;
+  const char *argv[] = { "octave", "--interactive", "--line-editing" };
+  octave_main (argc, (char **) argv, 1);
+  emit ready();
+  main_loop ();
+  clean_up_and_exit (0);
+}

new file mode 100644
--- /dev/null
+++ b/gui/src/OctaveMainThread.h
@@ -0,0 +1,20 @@
+#ifndef OCTAVEMAINTHREAD_H
+#define OCTAVEMAINTHREAD_H
+
+#include <QThread>
+#include "OctaveLink.h"
+
+class OctaveMainThread:public QThread
+{
+  Q_OBJECT
+public:
+  OctaveMainThread (QObject * parent);
+
+signals:
+  void ready();
+
+protected:
+  void run ();
+};
+
+#endif // OCTAVEMAINTHREAD_H