Starting from version 6.1.5 WebSphere Portal ships with Dojo 1.3.2 in addition to Dojo version 1.1.1. Starting from portal 6.1 dojo version 1.1.1 is shiped as part of the wps.ear, to be precise it is in wp_profile\installedApps\sunpa\wps.ear\wps.war\themes\dojo\portal_dojo folder, IBM kept it as it is.
In order to include Dojo 1.3.2 they create a Dojo_Resources.ear file which has 1.3.2 version of the dojo
The Dojo_Resources.ear has new version of dojo and few additional dojo classes created by IBM, these classes implement some of the IBM's client side logic. This enterprise application does not have any java classes so its used only for making dojo resources accessible.
As you can see the Dojo_Resources.war is available at /portal_dojo path. The dojo client side theme loads dojo from this path
As you can see the value of baseUrl property in the djConfig is /portal_dojo/dojo/, that means dojo is loaded from this location. You can see that even the tundra.css or other dijit related resources are loaded from Dojo_Resources.war.
You can verify the dojo version by looking at dojo.version properties. As you can see we are using 1.3.2 version