Unable to index the entire farm on Solr if you create at least one subwiki or workspace

Steps to reproduce:

• Setup XEM by using the war file, Tomcat and HyperSQL
• Start XWiki and use the DW to install the UI
• Install the workspace template
• Create a new workspace by using the "Add" menu or a new subwiki by using the Wiki Manager
• Go to Administration -> Search, select Solr as the default search engine and click "Save"
• Select "Add to index" or Reindex for action, "Entire farm" for wiki and click Apply

You'll get a "Failed to execute the [velocity] macro" error on the wiki page and

2013-05-31 12:28:32,802 [http://192.168.0.40:8080/xwiki/bin/admin/XWiki/XWikiPreferences?editor=globaladmin&section=Search] ERROR o.x.v.i.DefaultVelocityEngine
 - Exception in macro #handleAction called at xwiki:XWiki.SolrSearchAdmin[line 4, column 1]

in the console.