SearchCustomField

The simple patch below allows you to search on custom fields with the syntax .fieldName:value. The : is chosen to match fulltext, although a delimiting = may be clearer for your users. This was done so that I could add a "Tags" custom field to queues for free from annotation & searching of tickets with relationships that cannot be represented with links (but perhaps queues, at the expense of manageability)

--- /tmp/Googleish.pm   2008-09-08 12:37:19.000000000 -0400
+++ lib/RT/Search/Googleish.pm  2008-09-08 12:44:21.000000000 -0400
@@ -141,6 +141,10 @@
             push @owner_clauses, "Owner = '" . $User->Name . "'";
         }

+        elsif ( $key =~ /\.(\w+):(\w+)/i ) {
+            push @user_clauses, "CF.{$1} LIKE '$2'";
+        }
+
         # Else, subject must contain $key
         else {
             $key =~ s/['\\].*//g;
[

An earlier incarnation matched

/cf.(\w+):(\w+)/i</

but this seemed unnecessarily verbose.

You may also want to add this patch which includes some rudimentary instructions for users

+++ share/html/Search/Simple.html       2008-09-08 13:21:17.000000000 -0400
@@ -58,6 +58,8 @@

 <p><&|/l&>Search for tickets. Enter <strong>id</strong> numbers, <strong>queues</strong> by name, Owners by <strong>username</strong> and Requestors by <strong>email address</strong>.</&></p>

+<p><&|/l&>Searching custom field values can be done, though it may take a long time if other constraints are not applied. To do so, search with <b>.CFName:<i>word</i></b>. e.g; <tt>.tags:spam</tt></&></p>
+
 <p><&|/l&>Searching the full text of every ticket can take a long time, but if you need to do it, you can search for any word in full ticket history for any word by typing <b>fulltext:<i>word</i></b>.</&></p>
 <p><&|/l&>RT will look for anything else you enter in ticket subjects.</&></p>

OR, you might install RTx:Tags, which provides this functionality and more, sans patches.