diff --git a/rhodecode/templates/compare/compare_cs.html b/rhodecode/templates/compare/compare_cs.html
--- a/rhodecode/templates/compare/compare_cs.html
+++ b/rhodecode/templates/compare/compare_cs.html
@@ -6,7 +6,7 @@
   %else:
     %for cnt, cs in enumerate(c.cs_ranges):
         <tr>
-        <td><div class="gravatar"><img alt="gravatar" src="${h.gravatar_url(h.email(cs.author),14)}"/></div></td>
+        <td><div class="gravatar"><img alt="gravatar" src="${h.gravatar_url(h.email_or_none(cs.author),14)}"/></div></td>
         <td>
           %if cs.raw_id in c.statuses:
             <div title="${c.statuses[cs.raw_id][1]}" class="changeset-status-ico"><img src="${h.url('/images/icons/flag_status_%s.png' % c.statuses[cs.raw_id][0])}" /></div>