diff --git a/ext/gd/libgd/gd_topal.c b/ext/gd/libgd/gd_topal.c
index 2d7db8c73fa..d2cd13f5b9e 100644
--- a/ext/gd/libgd/gd_topal.c
+++ b/ext/gd/libgd/gd_topal.c
@@ -772,6 +772,7 @@ LOCAL (void)
       nim->green[icolor] = 255;
       nim->blue[icolor] = 255;
     }
+		nim->open[icolor] = 0;
 #endif
 }