diff --git a/src/frontends/qt4/GuiPrefs.cpp b/src/frontends/qt4/GuiPrefs.cpp
index 679ad15a45..7e107d8ffb 100644
--- a/src/frontends/qt4/GuiPrefs.cpp
+++ b/src/frontends/qt4/GuiPrefs.cpp
@@ -716,16 +716,16 @@ void PrefScreenFonts::apply(LyXRC & rc) const
 
 	rc.zoom = screenZoomSB->value();
 	rc.dpi = screenDpiSB->value();
-	rc.font_sizes[FONT_SIZE_TINY] = widgetToDoubleStr(screenTinyED);
-	rc.font_sizes[FONT_SIZE_SCRIPT] = widgetToDoubleStr(screenSmallestED);
-	rc.font_sizes[FONT_SIZE_FOOTNOTE] = widgetToDoubleStr(screenSmallerED);
-	rc.font_sizes[FONT_SIZE_SMALL] = widgetToDoubleStr(screenSmallED);
-	rc.font_sizes[FONT_SIZE_NORMAL] = widgetToDoubleStr(screenNormalED);
-	rc.font_sizes[FONT_SIZE_LARGE] = widgetToDoubleStr(screenLargeED);
-	rc.font_sizes[FONT_SIZE_LARGER] = widgetToDoubleStr(screenLargerED);
-	rc.font_sizes[FONT_SIZE_LARGEST] = widgetToDoubleStr(screenLargestED);
-	rc.font_sizes[FONT_SIZE_HUGE] = widgetToDoubleStr(screenHugeED);
-	rc.font_sizes[FONT_SIZE_HUGER] = widgetToDoubleStr(screenHugerED);
+	rc.font_sizes[FONT_SIZE_TINY] = fromqstr(screenTinyED->text());
+	rc.font_sizes[FONT_SIZE_SCRIPT] = fromqstr(screenSmallestED->text());
+	rc.font_sizes[FONT_SIZE_FOOTNOTE] = fromqstr(screenSmallerED->text());
+	rc.font_sizes[FONT_SIZE_SMALL] = fromqstr(screenSmallED->text());
+	rc.font_sizes[FONT_SIZE_NORMAL] = fromqstr(screenNormalED->text());
+	rc.font_sizes[FONT_SIZE_LARGE] = fromqstr(screenLargeED->text());
+	rc.font_sizes[FONT_SIZE_LARGER] = fromqstr(screenLargerED->text());
+	rc.font_sizes[FONT_SIZE_LARGEST] = fromqstr(screenLargestED->text());
+	rc.font_sizes[FONT_SIZE_HUGE] = fromqstr(screenHugeED->text());
+	rc.font_sizes[FONT_SIZE_HUGER] = fromqstr(screenHugerED->text());
 	rc.use_pixmap_cache = pixmapCacheCB->isChecked();
 
 	if (rc.font_sizes != oldrc.font_sizes
@@ -758,16 +758,16 @@ void PrefScreenFonts::update(LyXRC const & rc)
 
 	screenZoomSB->setValue(rc.zoom);
 	screenDpiSB->setValue(rc.dpi);
-	doubleToWidget(screenTinyED, rc.font_sizes[FONT_SIZE_TINY]);
-	doubleToWidget(screenSmallestED, rc.font_sizes[FONT_SIZE_SCRIPT]);
-	doubleToWidget(screenSmallerED, rc.font_sizes[FONT_SIZE_FOOTNOTE]);
-	doubleToWidget(screenSmallED, rc.font_sizes[FONT_SIZE_SMALL]);
-	doubleToWidget(screenNormalED, rc.font_sizes[FONT_SIZE_NORMAL]);
-	doubleToWidget(screenLargeED, rc.font_sizes[FONT_SIZE_LARGE]);
-	doubleToWidget(screenLargerED, rc.font_sizes[FONT_SIZE_LARGER]);
-	doubleToWidget(screenLargestED, rc.font_sizes[FONT_SIZE_LARGEST]);
-	doubleToWidget(screenHugeED, rc.font_sizes[FONT_SIZE_HUGE]);
-	doubleToWidget(screenHugerED, rc.font_sizes[FONT_SIZE_HUGER]);
+	screenTinyED->setText(toqstr(rc.font_sizes[FONT_SIZE_TINY]));
+	screenSmallestED->setText(toqstr(rc.font_sizes[FONT_SIZE_SCRIPT]));
+	screenSmallerED->setText(toqstr(rc.font_sizes[FONT_SIZE_FOOTNOTE]));
+	screenSmallED->setText(toqstr(rc.font_sizes[FONT_SIZE_SMALL]));
+	screenNormalED->setText(toqstr(rc.font_sizes[FONT_SIZE_NORMAL]));
+	screenLargeED->setText(toqstr(rc.font_sizes[FONT_SIZE_LARGE]));
+	screenLargerED->setText(toqstr(rc.font_sizes[FONT_SIZE_LARGER]));
+	screenLargestED->setText(toqstr(rc.font_sizes[FONT_SIZE_LARGEST]));
+	screenHugeED->setText(toqstr(rc.font_sizes[FONT_SIZE_HUGE]));
+	screenHugerED->setText(toqstr(rc.font_sizes[FONT_SIZE_HUGER]));
 
 	pixmapCacheCB->setChecked(rc.use_pixmap_cache);
 #if defined(Q_WS_X11)
@@ -1200,7 +1200,7 @@ PrefConverters::PrefConverters(GuiPreferences * form)
 void PrefConverters::apply(LyXRC & rc) const
 {
 	rc.use_converter_cache = cacheCB->isChecked();
-	rc.converter_cache_maxage = int(widgetToDouble(maxAgeLE) * 86400.0);
+	rc.converter_cache_maxage = int(maxAgeLE->text().toDouble() * 86400.0);
 }
 
 
@@ -1208,7 +1208,8 @@ void PrefConverters::update(LyXRC const & rc)
 {
 	cacheCB->setChecked(rc.use_converter_cache);
 	QString max_age;
-	doubleToWidget(maxAgeLE, (double(rc.converter_cache_maxage) / 86400.0), 'g', 6);
+	max_age.setNum(double(rc.converter_cache_maxage) / 86400.0, 'g', 6);
+	maxAgeLE->setText(max_age);
 	updateGui();
 }