diff --git a/doc/docbook/acegi.xml b/doc/docbook/acegi.xml
index 8dce5b71ec..108f32235b 100644
--- a/doc/docbook/acegi.xml
+++ b/doc/docbook/acegi.xml
@@ -405,6 +405,65 @@
context property on the
HttpSessionContextIntegrationFilter bean.
+
+
+ Localization
+
+ From 1.0.0, Acegi Security supports localization of exception
+ messages that end users are likely to see. Such exceptions include
+ authentication failures and access being denied (authorization
+ failures). Exceptions and logging that is focused on developers or
+ system deployers (including incorrect attributes, interface contract
+ violations, using incorrect constructors, startup time validation,
+ debug-level logging) etc are not localized and instead are hard-coded
+ in English within Acegi Security's code.
+
+ Shipping in the acegi-security-xx.jar inside
+ the org.acegisecurity package is a
+ messages.properties file. This should be referred
+ to by your ApplicationContext, as Acegi Security
+ classes implement Spring's MessageSourceAware
+ interface and expect the message resolver to be dependency injected at
+ application context startup time. Usually all you need to do is
+ register a bean inside your application context to refer to the
+ messages. An example is shown below:
+
+ <bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
+ <property name="basename"><value>org/acegisecurity/messages</value></property>
+</bean>
+
+ The messages.properties is named in
+ accordance with standard resource bundles and represents the default
+ language supported by Acegi Securtiy messages. This default file is in
+ English. If you do not register a message source, Acegi Security will
+ still work correctly and fallback to hard-coded English versions of
+ the messages.
+
+ If you wish to customize the
+ messages.properties file, or support other
+ languages, you should copy the file, rename it accordingly, and
+ register it inside the above bean definition. There are not a large
+ number of message keys inside this file, so localization should not be
+ considered a major initiative. If you do perform localization of this
+ file, please consider sharing your work with the community by logging
+ a JIRA task and attaching your appropriately-named localized version
+ of messages.properties.
+
+ Rounding out the discussion on localization is the Spring
+ ThreadLocal known as
+ org.springframework.context.i18n.LocaleContextHolder.
+ You should set the LocaleContextHolder to represent
+ the preferred Locale of each user. Acegi Security
+ will attempt to locate a message from the message source using the
+ Locale obtained from this
+ ThreadLocal. Please refer to Spring documentation
+ for further details on using LocaleContextHolder
+ and the helper classes that can automatically set it for you (eg
+ AcceptHeaderLocaleResolver,
+ CookieLocaleResolver,
+ FixedLocaleResolver,
+ SessionLocaleResolver etc)
+