mod_smacks: Fix traceback due to session being destroyed in send() Sending something can cause the OS to notice that the connection is dead and then the connection can be dead at this point. More likely if opportunistic_writes is enabled.

This module lets you block connections to remote servers at the s2s
level.

``` {.lua}
s2s_blacklist = {
    "proxy.eu.jabber.org",
}
```