Why doesn't Apache Shiro's [anon] Filter work correctly?

I tried to use authentication with Apache Shiro on my project, but without succes. I can’t discover where is the trouble. I need only that whoever user access the page /pages/principal/products.xhtml directly, choose the product to buy and then be redirect to /purchase.xhtml to finish the purchase, but in my case all requests that I try are redirect to /login.xhtml page. Does anyone have any suggestions? code below. thanks!

shiro.ini    
[main]
authc.loginUrl = /login.xhtml
authc.successUrl = /index.xhtml

[users]
[email protected] = adminfaces, admin
[email protected] = user, customer


[roles]
admin = *
customer = purchases

[urls]

/index.xhtml = anon
/pages/principal/products = anon
/login.xhtml = authc
/javax.faces.resource/** = anon
/logout = logout
/pages/purchase/** = authc
/protected/** = authc, roles[admin]

web.xml

...
<listener>
    <listener-class>org.apache.shiro.web.env.EnvironmentLoaderListener
    </listener-class>
</listener>

<filter>
    <filter-name>ShiroFilter</filter-name>
    <filter-class>org.apache.shiro.web.servlet.ShiroFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>ShiroFilter</filter-name>
    <url-pattern>/*</url-pattern>
    <dispatcher>REQUEST</dispatcher>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>INCLUDE</dispatcher>
    <dispatcher>ERROR</dispatcher>
</filter-mapping>
...