Glance with S3 backend store

Hi,

I've successfully installed Glance. I've already tested it with the filesystem backend and it works fine. Although now I was trying to upload images to S3. For that I've edited the following glance-api.conf attributtes:

===========

default_store = s3
...
s3_store_host = s3.amazonaws.com
s3_store_access_key = XXXXXXX
s3_store_secret_key = XXXXXXX

============

I've saved the file and restarted the glance-api. Then I try:

glance add name="image S3" is_public=true < sample.iso

But I get:

==========================
Uploading image 'image S3'
Failed to add image. Got error:
Data supplied was not valid.
Details: 400 Bad Request

The server could not comply with the request since it is either malformed or otherwise incorrect.

 Error uploading image: (S3ResponseError): S3ResponseError: 403 Forbidden RequestTimeTooSkewedThe difference between the request time and the current time is too large.900000B941EA68EBC60960qJ9rCPcF+NJQFL9Bni11a4t0WhSSrgZJkOtrY09o1q4MVKNM29c60+ZLJ3JRY18dFri, 22 Jun 2012 05:07:46 GMT2012-07-02T15:25:37Z
Note: Your image metadata may still be in the registry, but the image's status will likely be 'killed'.
====================

I've double checked the user credentials, they are ok. Any guess on what's happening there? I can't also refer to an S3 image with the "copy_from" option.

Another question, is there an option for uploading an image to a different backend than that elected as default on the .conf file? This is, a CLI option.