Babel over br-lan and export via bgp

[Oriol Rico]

Hello everybody
   I have a bird daemon with this configuration

# Configure logging
log syslog all;
log "/var/log/bird.log" all;
log stderr all;
#debug protocols { routes, interfaces };

# Override router ID
router id 10.20.2.2;

# Sync bird routing table with kernel
protocol kernel {
    learn;
    ipv4 {
        import all;
        export all;
    };
}

protocol device {
        scan time 10;
}

# Include directly connected networks
protocol direct {
       ipv4;
}

protocol static static4 {
    ipv4 { export all;};
    route 10.0.0.0/8 via 10.20.2.1;
    route 0.0.0.0/0 via 10.20.2.1;
}

protocol babel {
    interface "wlan0" {
        type wireless;
        hello interval 1 s;
        rx buffer 15000;
    };
    interface "br-lan" {
        type wired;
    };
    ipv4 {
export where (source = RTS_DEVICE) || (source = RTS_BABEL) || (source
= RTS_STATIC);
    };
}

filter rr_export {
if ( net ~ [ 10.0.0.0/8{24,32} ] ) then
           {
                accept;
           }
else{
reject;
}
}

protocol bgp {
        local 10.20.2.2 as 114108;
        source address 10.20.2.2;
        neighbor 10.20.2.1 as 111796;
        ipv4 {
            import none;
            export filter rr_export;
      };
}

    I received a route via br-lan with the prefix 10.20.3.32/27 via
babel protocol, but when i export via bgp the peer logs a Withdrawn,
but when i am in the router with the setup i send i can reach
10.20.3.32/27 via br-lan over babel.
    I don't know where is the problem. All other config it's ok.
    Can you help me?

Thanks in advanced

Oriol