I am facing issues in publishing images

When I use uec-publish-tarball, I get the following error

uec-publish-tarball ubuntu1010-UEC-localuser-image.tar.gz mybucket x86_64 Wed Mar 16 19:20:35 IST 2011: ====== extracting image ====== Warning: no ramdisk found, assuming '--ramdisk none' kernel : maverick-server-uec-amd64-vmlinuz-virtual ramdisk: none image : maverick-server-uec-amd64.img Wed Mar 16 19:21:20 IST 2011: ====== bundle/upload kernel ====== failed to register maverick-server-uec-amd64-vmlinuz-virtual.manifest.xml failed: euca-register mybucket/maverick-server-uec-amd64-vmlinuz-virtual.manifest.xml UnknownError: An unknown error has occurred. Please try your request again.failed to upload kernel

2011-03-16 23:08:57,863 AUDIT nova.api [H5EOMCF42XGOZIS13SFR georgy minor] Authenticated Request For georgy:minor) 2011-03-16 23:08:57,863 DEBUG nova.api [-] action: RegisterImage from (pid=8036) __call__ /usr/lib/pymodules/python2.6/nova/api/ec2/__init__.py:213 2011-03-16 23:08:57,864 DEBUG nova.api [-] arg: ImageLocation val: mybucket/maverick-server-uec-amd64-vmlinuz-virtual.manifest.xml from (pid=8036) __call__ /usr/lib/pymodules/python2.6/nova/api/ec2/__init__.py:215 2011-03-16 23:08:58,029 ERROR nova.api [H5EOMCF42XGOZIS13SFR georgy minor] Unexpected error raised: 'NoneType' object has no attribute 'get_contents_as_string' (nova.api): TRACE: Traceback (most recent call last): (nova.api): TRACE: File "/usr/lib/pymodules/python2.6/nova/api/ec2/__init__.py", line 318, in __call__ (nova.api): TRACE: result = api_request.invoke(context) (nova.api): TRACE: File "/usr/lib/pymodules/python2.6/nova/api/ec2/apirequest.py", line 150, in invoke (nova.api): TRACE: result = method(context, **args) (nova.api): TRACE: File "/usr/lib/pymodules/python2.6/nova/api/ec2/cloud.py", line 921, in register_image (nova.api): TRACE: image = self.image_service.create(context, metadata) (nova.api): TRACE: File "/usr/lib/pymodules/python2.6/nova/image/s3.py", line 56, in create (nova.api): TRACE: image = self._s3_create(context, metadata) (nova.api): TRACE: File "/usr/lib/pymodules/python2.6/nova/image/s3.py", line 139, in _s3_create (nova.api): TRACE: manifest = key.get_contents_as_string() (nova.api): TRACE: AttributeError: 'NoneType' object has no attribute 'get_contents_as_string' (nova.api): TRACE: 2011-03-16 23:08:58,030 ERROR nova.api [H5EOMCF42XGOZIS13SFR georgy minor] Environment: {"HTTP_AUTHORIZATION": "AWS 946b58a6-8353-4bbb-877e-85e1e21ac4ff:minor:P5yBjkWDNK3S+utGgcn5j2NCTAo=", "SCRIPT_NAME": "/services/Cloud", "REQUEST_METHOD": "GET", "PATH_INFO": "/", "SERVER_PROTOCOL": "HTTP/1.0", "QUERY_STRING": "AWSAccessKeyId=946b58a6-8353-4bbb-877e-85e1e21ac4ff%3Aminor&Action=RegisterImage&ImageLocation=mybucket%2Fmaverick-server-uec-amd64-vmlinuz-virtual.manifest.xml&SignatureMethod=HmacSHA256&SignatureVersion=2&Timestamp=2011-03-16T17%3A38%3A57&Version=2009-11-30&Signature=xG%2BzzdUNL4bPYeH44OQwDNcGAgcWBlz6Mccdh3yBmJg%3D", "CONTENT_LENGTH": "0", "HTTP_USER_AGENT": "Boto/1.9b (linux2)", "HTTP_CONNECTION": "keep-alive", "SERVER_NAME": "10.20.254.59", "REMOTE_ADDR": "10.10.78.62", "wsgi.url_scheme": "http", "HTTP_VIA": "1.1 proxy62.iitd.ernet.in:3128 (squid/2.7.STABLE7)", "SERVER_PORT": "8773", "HTTP_DATE": "Wed, 16 Mar 2011 17:38:57 GMT", "HTTP_HOST": "10.20.254.59:8773", "HTTP_CACHE_CONTROL": "max-age=259200", "GATEWAY_INTERFACE": "CGI/1.1", "HTTP_X_FORWARDED_FOR": "10.20.254.59", "CONTENT_TYPE": "text/plain", "HTTP_ACCEPT_ENCODING": "identity"} 2011-03-16 23:08:58,030 ERROR nova.api [H5EOMCF42XGOZIS13SFR georgy minor] UnknownError: An unknown error has occurred. Please try your request again. 2011-03-16 23:08:58,030 INFO nova.api [H5EOMCF42XGOZIS13SFR georgy minor] 0.246829s 10.10.78.62 GET / None:None 400 [Boto/1.9b (linux2)] text/plain text/xml 2011-03-16 23:08:58,315 DEBUG nova ... (more)