SQL Error when comment module is not installed

I tested the development version (7.x-2.x-dev, datestamp 1285374359) on a setup
that does not need any comments and thus has the comment module uninstalled.
When I run cron I get the following SQL error:

PDOException: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'schlafportal.comment' doesn't exist: SELECT c.created FROM {comment} c WHERE c.nid = :nid AND c.status = :status UNION ALL SELECT nr.timestamp FROM {node_revision} nr WHERE nr.nid = :nid2; Array ( [:nid] => 25 [:status] => COMMENT_PUBLISHED [:nid2] => 25 ) in xmlsitemap_node_get_timestamps() (line 159 of /mypath/sites/all/modules/contrib/xmlsitemap/xmlsitemap_node/xmlsitemap_node.module).