Ask.com has implemented pinging service to support for the Sitemaps protocol autodiscovery that they left behind in April.
How does it work? From Ask's help files:
Once you have prepared the sitemap, add the sitemap auto-discovery directive to robots.txt as follows:
SITEMAP: http://www.the URL of your sitemap here.xml
The sitemap location should be the full sitemap URL. Alternatively, you can also submit your sitemap through the ping URL:
http://submissions.ask.com/ping?sitemap=http%3A//www.the URL of your sitemap here.xml
Please note that sitemap submissions do not guarantee the indexing of URLs. To learn more about the protocol, please visit the Sitemaps web site at http://www.sitemaps.org.
Ask.com, Sitemaps, Autodiscovery, Pinging, SEO
Source:? SEL Blog