How to add multiple custom-filter in Spring Security 3?

I need add two custom filters for FORM_LOGIN_FILTER, e.g.

<custom-filter after="FORM_LOGIN_FILTER" ref="myUsernamePasswordAuthenticationFilter" />
<custom-filter after="FORM_LOGIN_FILTER" ref="myUsernamePasswordAuthenticationFilter2" />

What I expect the filter sequences is:
1. Predefind FORM_LOGIN_FILTER
2. myUsernamePasswordAuthenticationFilter
3. myUsernamePasswordAuthenticationFilter2

But above will cause configuration error. So, anyone knows how to write the right config? Thanks!