--- a/src/iconolab/templates/iconolab/detail_item.html	Thu Oct 06 16:48:36 2016 +0200
+++ b/src/iconolab/templates/iconolab/detail_item.html	Mon Oct 10 10:46:56 2016 +0200
@@ -10,7 +10,7 @@
 <div id="item-detail" class="row">
 	<div class="col-md-6">
         {% for image in images|dictsort:"obj.pk" %}
-          <div id="img-{{image.obj.image_guid}}" class="item-detail-image-block {% if image.obj.image_guid == display_image %}selected{% endif %}">
+          <div id="img-{{image.obj.image_guid}}" class="item-detail-image-block {% ifequal image.obj.image_guid|stringformat:'s' display_image %}selected{% endifequal %}">
     		{% thumbnail image.obj.media "500x500" crop=False as im %}
   			   <img src="{{ im.url }}" width="{{ im.width }}" height="{{ im.height }}">
     		{% endthumbnail %}