diff --git a/src/kits/interface/Window.cpp b/src/kits/interface/Window.cpp
index 6608c7c9f1..1b6a7e1dec 100644
--- a/src/kits/interface/Window.cpp
+++ b/src/kits/interface/Window.cpp
@@ -1533,12 +1533,13 @@ BWindow::Zoom()
 	
 	// fallback in case retrieving the decorator settings fails (highly unlikely)
 	float borderWidth = 5.0;
-	float tabHeight = 26.0;
+	float tabHeight = 21.0;
 	BMessage settings;
 	if (GetDecoratorSettings(&settings) == B_OK) {
 		BRect tabRect;
 		if (settings.FindRect("tab frame", &tabRect) == B_OK)
 			tabHeight = tabRect.Height();
+		settings.FindFloat("border width", &borderWidth);
 	}
 		
 	// 1) the rectangle defined by SetZoomLimits(),
@@ -1554,13 +1555,13 @@ BWindow::Zoom()
 	// 3) the screen rectangle
 	BScreen screen(this);
 	float screenWidth = screen.Frame().Width() - 2 * borderWidth;
-	float screenHeight = screen.Frame().Height() - (borderWidth + tabHeight);
+	float screenHeight = screen.Frame().Height() - (2 * borderWidth + tabHeight);
 	if (screenWidth < zoomedWidth)
 		zoomedWidth = screenWidth;
 	if (screenHeight < zoomedHeight)
 		zoomedHeight = screenHeight;
 
-	BPoint zoomedLeftTop = screen.Frame().LeftTop() + BPoint(borderWidth, tabHeight);
+	BPoint zoomedLeftTop = screen.Frame().LeftTop() + BPoint(borderWidth, tabHeight + borderWidth);
 
 	// UN-ZOOM:
 	if (fPreviousFrame.IsValid()
diff --git a/src/servers/app/DefaultDecorator.cpp b/src/servers/app/DefaultDecorator.cpp
index b0bb79095e..e2754e0598 100644
--- a/src/servers/app/DefaultDecorator.cpp
+++ b/src/servers/app/DefaultDecorator.cpp
@@ -449,6 +449,9 @@ DefaultDecorator::GetSettings(BMessage* settings) const
 	if (settings->AddRect("tab frame", fTabRect) != B_OK)
 		return false;
 
+	if (settings->AddFloat("border width", fBorderWidth) != B_OK)
+		return false;
+
 	return settings->AddFloat("tab location", (float)fTabOffset) == B_OK;
 }