HTTP ERROR: 404 missing core name in path after integrating nutch

[Ian M. Evans]

Hi everyone,

Last night I was able to get solr up and running. Ran and was able to 
access:

http://localhost:8983/solr/admin

This morning, I started on the nutch crawling instructions over at:

http://www.lucidimagination.com/blog/2009/03/09/nutch-solr/

After adding the following to /solr/conf/solrconfig.xml:
<requestHandler name="/nutch" class="solr.SearchHandler" >
<lst name="defaults">
<str name="defType">dismax</str>
<str name="echoParams">explicit</str>
<float name="tie">0.01</float>
<str name="qf">
content^0.5 anchor^1.0 title^1.2
</str>
<str name="pf">
content^0.5 anchor^1.5 title^1.2 site^1.5
</str>
<str name="fl">
url
</str>
<str name="mm">
2&lt;-1 5&lt;-2 6&lt;90%
</str>
<int name="ps">100</int>
<bool hl="true"/>
<str name="q.alt">*:*</str>
<str name="hl.fl">title url content</str>
<str name="f.title.hl.fragsize">0</str>
<str name="f.title.hl.alternateField">title</str>
<str name="f.url.hl.fragsize">0</str>
<str name="f.url.hl.alternateField">url</str>
<str name="f.content.hl.fragmenter">regex</str>
</lst>
</requestHandler>

going to http://localhost:8983/solr/admin suddenly throws a "HTTP ERROR: 
404 missing core name in path"

Why would adding the above snippet suddenly throw that error?

Thanks.