What steps will reproduce the problem?

1. Just invoke the getFeed(Query query, Class<F> feedClass) method in 
com.google.gdata.client.contacts.ContactsService

with feedClass = com.google.gdata.data.contacts.ContactFeed.class
and query =
https://www.google.com/m8/feeds/contacts/fk@domainname.eu/full?start-index=1&max
-results=2500&group=https%3A%2F%2Fwww.google.com%2Fm8%2Ffeeds%2Fgroups%2Ffk%2540
domainname.eu%2Fbase%2F13bd1d8f0d94aab1&showdeleted=false&xoauth_requestor_id=fk
%40domainname.eu

What is the expected output? What do you see instead?

The expected output is a ContactFeed object, but we got this exception instead:
com.google.gdata.util.ParseException: The prefix "atom" for element "atom:cc" 
is not bound.
at com.google.gdata.util.XmlParser.parse(XmlParser.java:695)
at com.google.gdata.util.XmlParser.parse(XmlParser.java:568)
at com.google.gdata.data.BaseFeed.parseAtom(BaseFeed.java:793)
at 
com.google.gdata.wireformats.input.AtomDataParser.parse(AtomDataParser.java:68)
at 
com.google.gdata.wireformats.input.AtomDataParser.parse(AtomDataParser.java:39)
at 
com.google.gdata.wireformats.input.CharacterParser.parse(CharacterParser.java:10
0)
at 
com.google.gdata.wireformats.input.XmlInputParser.parse(XmlInputParser.java:52)
at 
com.google.gdata.wireformats.input.AtomDualParser.parse(AtomDualParser.java:66)
at 
com.google.gdata.wireformats.input.AtomDualParser.parse(AtomDualParser.java:34)
at com.google.gdata.client.Service.parseResponseData(Service.java:1896)
at com.google.gdata.client.Service.getFeed(Service.java:1054)
at com.google.gdata.client.Service.getFeed(Service.java:995)
at com.google.gdata.client.GoogleService.getFeed(GoogleService.java:662)
at com.google.gdata.client.Service.getFeed(Service.java:952)

What version of the product are you using? On what operating system?
The version is v3.0 for java (gdata-contacts-3.0.jar), it is running on Google 
App Engine 1.5.4

Please provide any additional information below.
The application has been running for almost one year now, and is retrieving 
data from around 1500 domains, doing round robin with 20 domains each minute, 
with no major problems. But this is the first time we see this error.