diff --git a/src/cocoa/colour.mm b/src/cocoa/colour.mm
index b1aa432a3c..b191ab9a96 100644
--- a/src/cocoa/colour.mm
+++ b/src/cocoa/colour.mm
@@ -96,8 +96,8 @@ void wxColour::Set( WX_NSColor aColor )
        unless the color was actually RGB to begin with it's likely that
        these will be fairly bogus. Particulary if the color is a pattern. */
     NSColor *rgbColor = [m_cocoaNSColor colorUsingColorSpaceName:NSCalibratedRGBColorSpace];
-    m_red = [rgbColor redComponent]*255.0;
-    m_green = [rgbColor greenComponent]*255.0;
-    m_blue = [rgbColor blueComponent]*255.0;
+    m_red 	= (wxUint8) ([rgbColor redComponent]   * 255.0);
+    m_green = (wxUint8) ([rgbColor greenComponent] * 255.0);
+    m_blue 	= (wxUint8) ([rgbColor blueComponent]  * 255.0);
 }