diff --git a/src/frontends/qt4/Makefile.dialogs b/src/frontends/qt4/Makefile.dialogs
index 668e5c2cd7..aa65de0d6e 100644
--- a/src/frontends/qt4/Makefile.dialogs
+++ b/src/frontends/qt4/Makefile.dialogs
@@ -127,7 +127,7 @@ MOCFILES = \
 	QTabularCreateDialog.C QTabularCreateDialog.h \
 	QTabularDialog.C QTabularDialog.h \
 	QTexinfoDialog.C QTexinfoDialog.h \
-	QThesaurusDialog.C QThesaurusDialog.h \
+	QThesaurus.C QThesaurus.h \
 	TocModel.C TocModel.h \
 	TocWidget.C TocWidget.h \
 	QToc.C QToc.h \
diff --git a/src/frontends/qt4/QThesaurus.C b/src/frontends/qt4/QThesaurus.C
index 4e92c9ec1d..23de2813b3 100644
--- a/src/frontends/qt4/QThesaurus.C
+++ b/src/frontends/qt4/QThesaurus.C
@@ -11,22 +11,141 @@
 #include <config.h>
 
 #include "QThesaurus.h"
-#include "QThesaurusDialog.h"
 #include "Qt2BC.h"
 #include "qt_helpers.h"
+#include "debug.h"
 
 #include "controllers/ControlThesaurus.h"
 
+#include <QHeaderView>
 #include <QLineEdit>
 #include <QPushButton>
+#include <QTreeWidget>
+#include <QTreeWidgetItem>
+
+using std::string;
 
 namespace lyx {
 namespace frontend {
 
-typedef QController<ControlThesaurus, QView<QThesaurusDialog> > theasaurus_base_class;
+/////////////////////////////////////////////////////////////////////
+//
+// QTheasurusDialog
+//
+/////////////////////////////////////////////////////////////////////
+
+QThesaurusDialog::QThesaurusDialog(QThesaurus * form)
+	: form_(form)
+{
+	setupUi(this);
+
+	meaningsTV->setColumnCount(1);
+	meaningsTV->header()->hide();
+
+	connect(closePB, SIGNAL(clicked()),
+		form, SLOT(slotClose()));
+	connect(replaceED, SIGNAL(returnPressed()),
+		this, SLOT(replaceClicked()));
+	connect(replaceED, SIGNAL(textChanged(const QString &)),
+		this, SLOT(change_adaptor() ) );
+	connect(entryED, SIGNAL(returnPressed()),
+		this, SLOT(entryChanged()));
+	connect(replacePB, SIGNAL(clicked()),
+		this, SLOT(replaceClicked()));
+	connect(meaningsTV, SIGNAL(itemClicked(QTreeWidgetItem *, int)),
+		this, SLOT(itemClicked(QTreeWidgetItem *, int)));
+	connect(meaningsTV, SIGNAL(itemSelectionChanged()),
+		this, SLOT(selectionChanged()));
+	connect(meaningsTV, SIGNAL(itemActivated(QTreeWidgetItem *, int)),
+		this, SLOT(selectionClicked(QTreeWidgetItem *, int)));
+}
+
+
+void QThesaurusDialog::change_adaptor()
+{
+	form_->changed();
+}
+
+
+void QThesaurusDialog::closeEvent(QCloseEvent * e)
+{
+	form_->slotWMHide();
+	e->accept();
+}
+
+
+void QThesaurusDialog::entryChanged()
+{
+	updateLists();
+}
+
+
+void QThesaurusDialog::replaceClicked()
+{
+	form_->replace();
+}
+
+
+void QThesaurusDialog::selectionChanged()
+{
+	int const col = meaningsTV->currentColumn();
+	if (col<0 || form_->readOnly())
+		return;
+
+	replaceED->setText(meaningsTV->currentItem()->text(col));
+	replacePB->setEnabled(true);
+	form_->changed();
+}
+
+
+void QThesaurusDialog::itemClicked(QTreeWidgetItem * /*item*/, int /*col*/)
+{
+	selectionChanged();
+}
+
+
+void QThesaurusDialog::selectionClicked(QTreeWidgetItem * item, int col)
+{
+	entryED->setText(item->text(col));
+	selectionChanged();
+	updateLists();
+}
+
+
+void QThesaurusDialog::updateLists()
+{
+	meaningsTV->clear();
+	meaningsTV->setUpdatesEnabled(false);
+
+	Thesaurus::Meanings meanings = form_->controller().getMeanings(qstring_to_ucs4(entryED->text()));
+
+	for (Thesaurus::Meanings::const_iterator cit = meanings.begin();
+		cit != meanings.end(); ++cit) {
+		QTreeWidgetItem * i = new QTreeWidgetItem(meaningsTV);
+		i->setText(0, toqstr(cit->first));
+		meaningsTV->expandItem(i);
+		for (std::vector<docstring>::const_iterator cit2 = cit->second.begin();
+			cit2 != cit->second.end(); ++cit2) {
+				QTreeWidgetItem * i2 = new QTreeWidgetItem(i);
+				i2->setText(0, toqstr(*cit2));
+			}
+	}
+
+	meaningsTV->setUpdatesEnabled(true);
+	meaningsTV->update();
+}
+
+
+/////////////////////////////////////////////////////////////////////
+//
+// QThesuarus
+//
+/////////////////////////////////////////////////////////////////////
+
+typedef QController<ControlThesaurus, QView<QThesaurusDialog> > ThesaurusBase;
 
 QThesaurus::QThesaurus(Dialog & parent)
-	: theasaurus_base_class(parent, _("Thesaurus"))
+	: ThesaurusBase(parent, _("Thesaurus"))
 {
 }
 
@@ -57,3 +176,6 @@ void QThesaurus::replace()
 
 } // namespace frontend
 } // namespace lyx
+
+
+#include "QThesaurus_moc.cpp"
diff --git a/src/frontends/qt4/QThesaurus.h b/src/frontends/qt4/QThesaurus.h
index b31f16bf27..e4beedf21b 100644
--- a/src/frontends/qt4/QThesaurus.h
+++ b/src/frontends/qt4/QThesaurus.h
@@ -13,13 +13,41 @@
 #define QTHESAURUS_H
 
 #include "QDialogView.h"
-#include "QThesaurusDialog.h"
+#include "ui/ThesaurusUi.h"
+
+#include <QDialog>
+#include <QCloseEvent>
+
+
+class QTreeWidgetItem;
 
 namespace lyx {
 namespace frontend {
 
 class ControlThesaurus;
 
+class QThesaurus;
+
+class QThesaurusDialog : public QDialog, public Ui::QThesaurusUi {
+	Q_OBJECT
+public:
+	QThesaurusDialog(QThesaurus * form);
+
+	void updateLists();
+protected Q_SLOTS:
+	virtual void change_adaptor();
+	virtual void entryChanged();
+	virtual void replaceClicked();
+	virtual void selectionChanged();
+	virtual void selectionClicked(QTreeWidgetItem *, int);
+	virtual void itemClicked(QTreeWidgetItem *, int);
+protected:
+	virtual void closeEvent(QCloseEvent * e);
+private:
+	QThesaurus * form_;
+};
+
+
 ///
 class QThesaurus
 	: public QController<ControlThesaurus, QView<QThesaurusDialog> >
diff --git a/src/frontends/qt4/QThesaurusDialog.C b/src/frontends/qt4/QThesaurusDialog.C
deleted file mode 100644
index a28e5a029a..0000000000
--- a/src/frontends/qt4/QThesaurusDialog.C
+++ /dev/null
@@ -1,137 +0,0 @@
-/**
- * \file QThesaurusDialog.C
- * This file is part of LyX, the document processor.
- * Licence details can be found in the file COPYING.
- *
- * \author John Levon
- *
- * Full author contact details are available in file CREDITS.
- */
-
-#include <config.h>
-
-#include "QThesaurusDialog.h"
-#include "QThesaurus.h"
-#include "qt_helpers.h"
-#include "debug.h"
-
-#include "controllers/ControlThesaurus.h"
-
-#include <QCloseEvent>
-#include <QPushButton>
-#include <QTreeWidget>
-#include <QTreeWidgetItem>
-#include <QLineEdit>
-#include <QHeaderView>
-
-using std::string;
-
-namespace lyx {
-namespace frontend {
-
-
-QThesaurusDialog::QThesaurusDialog(QThesaurus * form)
-	: form_(form)
-{
-	setupUi(this);
-
-	meaningsTV->setColumnCount(1);
-	meaningsTV->header()->hide();
-
-	connect(closePB, SIGNAL(clicked()),
-		form, SLOT(slotClose()));
-	connect( replaceED, SIGNAL( returnPressed() ),
-		this, SLOT( replaceClicked() ) );
-	connect( replaceED, SIGNAL( textChanged(const QString&) ),
-		this, SLOT( change_adaptor() ) );
-	connect( entryED, SIGNAL( returnPressed() ),
-		this, SLOT( entryChanged() ) );
-	connect( replacePB, SIGNAL( clicked() ),
-		this, SLOT( replaceClicked() ) );
-	connect( meaningsTV, SIGNAL( itemClicked(QTreeWidgetItem * , int) ),
-		this, SLOT( itemClicked(QTreeWidgetItem * , int) ) );
-	connect( meaningsTV, SIGNAL( itemSelectionChanged() ),
-		this, SLOT( selectionChanged() ) );
-	connect( meaningsTV, SIGNAL( itemActivated(QTreeWidgetItem * , int) ),
-		this, SLOT( selectionClicked(QTreeWidgetItem *, int) ) );
-}
-
-
-void QThesaurusDialog::change_adaptor()
-{
-	form_->changed();
-}
-
-
-void QThesaurusDialog::closeEvent(QCloseEvent * e)
-{
-	form_->slotWMHide();
-	e->accept();
-}
-
-
-void QThesaurusDialog::entryChanged()
-{
-	updateLists();
-}
-
-
-void QThesaurusDialog::replaceClicked()
-{
-	form_->replace();
-}
-
-
-void QThesaurusDialog::selectionChanged()
-{
-	int const col = meaningsTV->currentColumn();
-	if (col<0 || form_->readOnly())
-		return;
-
-	replaceED->setText(meaningsTV->currentItem()->text(col));
-	replacePB->setEnabled(true);
-	form_->changed();
-}
-
-
-void QThesaurusDialog::itemClicked(QTreeWidgetItem * /*item*/, int /*col*/)
-{
-	selectionChanged();
-}
-
-
-void QThesaurusDialog::selectionClicked(QTreeWidgetItem * item, int col)
-{
-	entryED->setText(item->text(col));
-	selectionChanged();
-	updateLists();
-}
-
-
-void QThesaurusDialog::updateLists()
-{
-	meaningsTV->clear();
-	meaningsTV->setUpdatesEnabled(false);
-
-	Thesaurus::Meanings meanings = form_->controller().getMeanings(qstring_to_ucs4(entryED->text()));
-
-	for (Thesaurus::Meanings::const_iterator cit = meanings.begin();
-		cit != meanings.end(); ++cit) {
-		QTreeWidgetItem * i = new QTreeWidgetItem(meaningsTV);
-		i->setText(0, toqstr(cit->first));
-		meaningsTV->expandItem(i);
-		for (std::vector<docstring>::const_iterator cit2 = cit->second.begin();
-			cit2 != cit->second.end(); ++cit2) {
-				QTreeWidgetItem * i2 = new QTreeWidgetItem(i);
-				i2->setText(0, toqstr(*cit2));
-			}
-	}
-
-	meaningsTV->setUpdatesEnabled(true);
-	meaningsTV->update();
-}
-
-} // namespace frontend
-} // namespace lyx
-
-#include "QThesaurusDialog_moc.cpp"
diff --git a/src/frontends/qt4/QThesaurusDialog.h b/src/frontends/qt4/QThesaurusDialog.h
deleted file mode 100644
index e34f4f6ad9..0000000000
--- a/src/frontends/qt4/QThesaurusDialog.h
+++ /dev/null
@@ -1,49 +0,0 @@
-// -*- C++ -*-
-/**
- * \file QThesaurusDialog.h
- * This file is part of LyX, the document processor.
- * Licence details can be found in the file COPYING.
- *
- * \author John Levon
- *
- * Full author contact details are available in file CREDITS.
- */
-
-#ifndef QTHESAURUSDIALOG_H
-#define QTHESAURUSDIALOG_H
-
-#include "ui/ThesaurusUi.h"
-
-#include <QDialog>
-#include <QCloseEvent>
-
-class QTreeWidgetItem;
-
-namespace lyx {
-namespace frontend {
-
-class QThesaurus;
-
-class QThesaurusDialog : public QDialog, public Ui::QThesaurusUi {
-	Q_OBJECT
-public:
-	QThesaurusDialog(QThesaurus * form);
-
-	void updateLists();
-protected Q_SLOTS:
-	virtual void change_adaptor();
-	virtual void entryChanged();
-	virtual void replaceClicked();
-	virtual void selectionChanged();
-	virtual void selectionClicked(QTreeWidgetItem *, int);
-	virtual void itemClicked(QTreeWidgetItem *, int);
-protected:
-	virtual void closeEvent(QCloseEvent * e);
-private:
-	QThesaurus * form_;
-};
-
-} // namespace frontend
-} // namespace lyx
-
-#endif // QTHESAURUSDIALOG_H