Segfault when playing with DynamicLookupCommand

$ cat ../radsecproxy.conf
rewrite in_rewrite {
        removeAttribute 5
        addAttribute 4:11
        removeVendorAttribute 98
        removeVendorAttribute 99:100
        addVendorAttribute 99:101:47
}


LoopPrevention on
client 127.0.0.1 {
        type udp
        secret secret
        rewriteIn in_rewrite
        rewriteAttribute User-Name:/^(.*)@local$/\1@example.com/
}
server 127.0.0.2 {
        type UDP
        secret secret
        LoopPrevention off
}
server 127.0.0.3 {
        type UDP
        secret secret
}
server 127.0.0.10 {
        type udp
        port 4711
        secret secret2
        dynamicLookupCommand /bin/false
}

realm * {
        server 127.0.0.10
}
$ gdb --args ./radsecproxy -fc ../radsecproxy.conf -d 4
[...]
$ echo "User-Name=bob@foo.com,User-Password=hemligt" | radclient 127.0.0.1 auth secret
[...]
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fffeffff700 (LWP 10489)]
0x000000000040f6fd in addserverextraudp (conf=0x641840) at udp.c:320
320 switch (((struct hostportres *)list_first(conf->hostports)->data)->addrinfo->ai_family) {
(gdb) p conf
 = (struct clsrvconf *) 0x641840
(gdb) p conf->hostports
 = (struct list *) 0x0
(gdb) p *conf
 = {name = 0x634d10 "127.0.0.10", type = 0 '\000', pdef = 0x419260, hostsrc = 0x635e00,
  portsrc = 0x634d50 "4711", hostports = 0x0, secret = 0x634d70 "secret2", tls = 0x0,
  matchcertattr = 0x0, certcnregex = 0x0, certuriregex = 0x0, confrewritein = 0x0,
  confrewriteout = 0x0, confrewriteusername = 0x0, rewriteusername = 0x0,
  dynamiclookupcommand = 0x634d90 "/bin/false", statusserver = 0 '\000',
  retryinterval = 255 '\377', retrycount = 255 '\377', dupinterval = 0 '\000',
  certnamecheck = 1 '\001', addttl = 0 '\000', loopprevention = 255 '\377', rewritein = 0x0,
  rewriteout = 0x0, lock = 0x0, tlsconf = 0x0, clients = 0x0, servers = 0x641910,
  fticks_viscountry = 0x0}