bridge relay: "DirPort unreachable"

[Gitano <0xb8968b9e9190@xxxxxxxxxxxxxx>]

When I start my bridge relay on a dedicated server at home, I get this:

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May 31 11:34:28.207 [notice] Self-testing indicates your ORPort is
reachable from the outside. Excellent. Publishing server descriptor.
May 31 11:35:37.485 [notice] Performing bandwidth self-test...done.
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But after a while:

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May 31 11:53:47.477 [warn] Your server (*.*.*.*:80) has not managed to
confirm that its DirPort is reachable. Please check your firewalls,
ports, address, /etc/hosts file, etc.
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So I started debugging:

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May 31 11:53:23.284 [debug] connection_dir_client_reached_eof():
Received response from directory server '*.*.*.*:80': 404 "Not found"
May 31 11:53:23.285 [info] connection_dir_client_reached_eof(): Received
server info (size 0) from server '*.*.*.*:80'
May 31 11:53:23.285 [info] connection_dir_client_reached_eof(): Received
http status code 404 ("Not found") from server '*.*.*.*:80' while
fetching "/tor/server/authority.z". I'll try again soon.
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What does this mean?

I'm familiar with NAT and my "m0n0wall" firewall shows up the
connections to port 9001/9030 of the tor-server.

Here comes my '/etc/tor/torrc':

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SocksPort 0
SocksListenAddress 127.0.0.1
Log notice file /var/log/tor/notices.log
DataDirectory /var/lib/tor
Nickname ***
Address ***
HiddenServiceDir /var/lib/tor/hidden_service_www/
HiddenServicePort 80 127.0.0.1:80
ORPort 443
ORListenAddress 0.0.0.0:9001
DirPort 80
DirListenAddress 0.0.0.0:9030
BridgeRelay 1
PublishServerDescriptor bridge
RelayBandwidthRate 100 KB
RelayBandwidthBurst 100 KB
ExitPolicy reject *:*
TunnelDirConns 1
PreferTunneledDirConns 1
Log debug file /var/log/tor/debug.log
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