PG-9.0 - XML Data in a Column

Hi,

Is there a way to extract the contents of a column which is nothing but a well defined XML blob of data, and to be able to traverse the XML Elements ( XPath style) using any in-build functions ?

Also, how would I store such a XML blob in a column ?  Declare the column as 'VARCHAR(256)' or something else ?

Would this require any special module to be loaded at the Server startup ?  I am using the PG-9.0 Installer from the official site.

Thanks!
Arvind