--- lightbox2.module.orig	2009-10-25 17:01:44.609565400 +0100
+++ lightbox2.module	2009-10-25 17:01:51.860565400 +0100
@@ -643,7 +643,7 @@
     'font_color' => variable_get('lightbox2_font_color', '000'),
     'box_color' => variable_get('lightbox2_box_color', 'fff'),
     'top_position' => variable_get('lightbox2_top_position', ''),
-    'overlay_opacity' => variable_get('lightbox2_overlay_opacity', 0.8),
+    'overlay_opacity' => variable_get('lightbox2_overlay_opacity', '0.8'),
     'overlay_color' => variable_get('lightbox2_overlay_color', '000'),
     'disable_close_click' => variable_get('lightbox2_disable_close_click', TRUE),
     'resize_sequence' => variable_get('lightbox2_resize_sequence', 0),