Unable to retrieve spec for <path to gadget's XML>. HTTP error 504

Description of the bug/feature.
==================================

What steps will reproduce the problem?
======================================
From Calculated Passwords http://calculatedpass.com click "Add as iGoogle
Gadget". This opens up
http://www.google.com/ig/adde?moduleurl=calculatedpass.com/g/calculatedpass.xml

What is the expected output?
============================
The gadget content is displayed. 

What is the actual output?
==========================
"Unable to retrieve spec for
http://calculatedpass.com/g/calculatedpass.xml. HTTP error 504". Note that
the gadget can be added fine using this link or any other methods, such as
"Add stuff" from igoogle.com; it's the subsequent display at igoogle.com
that doesn't render any the content. 

Occasionally I am able to see the content off calculatedpass.com when I
continuously click the "Cache" checkbox in "My Gadgets". In other cases I
see the gadget partially rendered without CSS applied. I've never seen this
directly off http://calculatedpass.com 

Which browsers have you experienced this on?
============================================
IE 8 and FF 3.5.8. (not  relevant here) 

Which operating systems have you experienced this on?
=====================================================
Windows 7 and Linux FC 2.6.31.12-174.2.22.fc12.i686. (not relevant here)

Please provide any additional information below.
The addition from a mirror site
http://www.google.com/ig/adde?source=atgs&moduleurl=derivedpass.appspot.com/g/ca
lculatedpass.xml
works fine. Hosting company for calculatedpass.com indicates no issues.
Indeed, the http://calculatedpass.com is fully functional without a
browser, in particular and the XML file can be downloaded fine. Thank you
in advance.

Original issue reported on code.google.com by brain...@gmail.com on 10 Mar 2010 at 12:58

franky1978 / igoogle-legacy

Unable to retrieve spec for <path to gadget's XML>. HTTP error 504 #656