Need help with REST using Rails


I am using the rest_resource.rb file available from the article:

This script provides a method respond to a post request that sends an
XML to the server to update the database. It also responds to a get
request with a response containing an XML with data from the database.

I would like to use this between two processes, to synchronize two
remote databases. The processes, on one the client PC and one on the
server, will query each other to find what is new. So if there is a
change in the data on the PC, it has to POST and XML to the server with
the data containing the changes. The Server will then parse the XML and
update its database.

Can somebody tell me how to POST an XML to the server in Rails?