nofollow link relationship in generated html

I've enabled the "Include a stylesheet in the sitemaps for humans" configuration option. Each entry has a "nofollow" generated at line 110 of xmlsitemap.xml:

<a href="{$sitemapURL}" ref="nofollow"><xsl:value-of select="$sitemapURL"></xsl:value-of></a>

Two questions:
1. Isn't the attribute name wrong? Shouldn't it be "rel", not "ref"?
2. More importantly, why? I'd like to set up a Google Search Appliance to crawl my site. But won't it fail to index links with nofollow, defeating the utility of the sitemap for indexing?