diff --git a/doc/Readme.reg_agent.txt b/doc/Readme.reg_agent.txt
index 331cf039..967bd480 100644
--- a/doc/Readme.reg_agent.txt
+++ b/doc/Readme.reg_agent.txt
@@ -7,3 +7,6 @@ If the registration is not successful, it tries to
 re-register.
 
 This module depends on the registrar_client module.
+
+Loading uac_auth module is needed if the registration should
+be authenticated!
diff --git a/doc/Readme.registrar_client.txt b/doc/Readme.registrar_client.txt
index 40489169..c5bebde5 100644
--- a/doc/Readme.registrar_client.txt
+++ b/doc/Readme.registrar_client.txt
@@ -6,6 +6,9 @@ explicitely removed via "removeRegistration".
 
 It is invoked via DI API, or used by the reg_agent module.
 
+Loading uac_auth module is needed if the registration should
+be authenticated!
+
 API functions: 
 =============