Do you mean display the blocked category on the 'Access Denied' page that EFW displays ?
To do this will require some editing of files, you cannot do this from the web interface
I have changed my 'Access Denied' page to display :
Access to the page:
http://www.xxxxx.com.
... has been denied for the following reason:
Banned phrase found.
... in category:
Google Searches
Note the extra . at the end of the page url ! this is my secret bypass link
To do this I have ;
edit the /usr/share/dansguardian/languages/ukenglish/template.html file
you will need to add the following line to the Body section after the line : Bypass: -BYPASS-
Category: -CATEGORIES-
then edit your message page
Access to the page:
<P>
<strong><a href="-URL-">-URL-</a><a href="-BYPASS-">.</a></strong>
<P> ... has been denied for the following reason: <P>
<strong><font color="#000000">-REASONGIVEN-</font></strong>
<p>
<P> ... in category: <P>
<strong><font color="#000000">-CATEGORIES-</font></strong>
To get the bypass link to work you will need to edit the /etc/dansguardian/dansguardianf?.conf.tmpl where the ? is the filterlist profile number, for the default profile this will be 1 so dansguardianf1.conf.tmpl
change the line 'bypass = 0' to 'bypass = 300' for a 5 minute bypass link, note that this is not password protected so anyone who knows about your secret bypass link can use it
Hope this helps
Edit : Sorry forgot to mention that sometimes the Category will display : N/A as it is not known which category the page is in (could be in multiple black lists).