Adding custom module pages to the Solr index We're using Drupal 6.
I have written several custom modules that generate a number of pages. All the paths are "given" to drupal using hook_menu() so the system is fully aware of how to access them.

However, if I search for something that I know is on a page I have created with one of these custom modules, it does not appear in search results. We're building a lot of content using custom modules which are pulling data out of pre-existing databases. We need these to be searchable.

How can I add these new paths and the content on these pages into the Solr index?
Apache Solr Search Integration is a replacement for the core content search.
This means that the output of your custom modules will appear in the Solr index, if the modules create nodes.

If the content returned by the custom modules is dynamic, then they need to create dummy nodes that they will be updated with hook_nodeapi(). When ApacheSolr rebuilds its index, it loads the node with node_load(), which then invokes any implementation of hook_nodeapi(), passing "load" as operation parameter.