[acc] clarify need for extra radius dictionary

(cherry picked from commit 16590b880b69c258a54fa4a31ab3d5686fc42b86)

modules/acc/README

@@ -36,6 +36,7 @@ Irina-Maria Stanescu
               1.2.1. Overview
               1.2.2. Definitions and syntax
               1.2.3. How it works
+              1.2.4. Radius accounting dependencies
 
         1.3. Multi Call-Legs accounting
 
@@ -316,6 +317,12 @@ lag!)
    headers or AVPs). In this case, the returned values are
    embedded in a single string in a comma-separated format.
 
+1.2.4. Radius accounting dependencies
+
+   If radius accounting is used, except from a radius client which
+   is mandatory, dictionary.rfc2866 must be used in order for the
+   module to work properly.
+
 1.3. Multi Call-Legs accounting
 
 1.3.1. Overview

modules/acc/doc/acc_admin.xml

@@ -220,6 +220,13 @@ if (uri=~"sip:+40") /* calls to Romania */ {
 			embedded in a single string in a comma-separated format.
 			</para>
 		</section>
+		<section>
+			<title>Radius accounting dependencies</title>
+			<para>
+				If radius accounting is used, except from a radius client library which is mandatory,
+				<emphasis role='bold'>dictionary.rfc2866</emphasis> must be included for the module
+				to work properly.</para>
+		</section>
 	</section>
 
 	<section id="multi-call-legs">