Error in registering an image in Ubuntu

Hi there,
I get an error message when I register an image
( euca-register ubuntu-kernel-bucket5/vmlinuz-2.6.28-11-server.manifest.xml) the error message is like below
Warning: failed to parse error message from AWS: :1:0: syntax error
EC2ResponseError: 400 Bad Request
Failure: 400 Bad Request
Failed to bind the following fields:
Location = ubuntu-kernel-bucket5/vmlinuz-2.6.28-11-server.manifest.xml
Please help to resolve.
Thanks
