conditionally loading property files

[EJ Ciramella]

sorry, drumming this up again guys - so I have the following:
 
    <filters>
       <filter>src/main/filters/filter.properties</filter>
       <filter>${user.home}/${pom.name}.properties</filter>
 
<filter>${user.home}/${pom.name}-${pom.version}.properties</filter>
    </filters>
 
But if a file doesn't exist, maven fails.  How can I make maven just
continue if it doesn't exist instead of failing?