Lucid Imagination has a brief but helpful post on running Solr on Jetty. In ColdFusion 9, Solr runs on Jetty by default (at least under Windows – not sure about Linux or Solaris and I don’t have any information about CF 10). The jetty.xml file can be found under <CF_HOME>/solr/etc/jetty.xml. On a single-instance installation under Windows, then, it would be located under C:\ColdFusion9\solr\etc\jetty.xml.
In order to change the port on which Jetty listens, edit the following (lines 64-78 on the default CF Solr install):
<!-- Use this connector if NIO is not available. -->
<!-- This connector is currently being used for Solr because the
nio.SelectChannelConnector showed poor performance under WindowsXP
from a single client with non-persistent connections (35s vs ~3min)
to complete 10,000 requests)
-->
<Call name="addConnector">
<Arg>
<New class="org.mortbay.jetty.bio.SocketConnector">
<Set name="port"><SystemProperty name="jetty.port" default="8983"/></Set>
<Set name="maxIdleTime">50000</Set>
<Set name="lowResourceMaxIdleTime">1500</Set>
</New>
</Arg>
</Call>
Change the value of 8983 to a different port and then restart the ColdFusion Solr service. Solr should now be listening on a different port.