diff --git a/install/10.asterisk.md b/install/10.asterisk.md
index bd60b31ff..bd2a178c9 100644
--- a/install/10.asterisk.md
+++ b/install/10.asterisk.md
@@ -65,3 +65,41 @@ ln -sf /opt/rbt/install/logrotate/asterisk /etc/logrotate.d/asterisk
 ```bash
 systemctl enable asterisk --now
 ```
+
+## Custom scripts
+
+You can use custom Lua scripts, which should be placed in `/etc/asterisk/custom`. This can be useful if you want to
+extend the standard behavior or replace parts of the dialplan. Custom script names should be listed in the `custom`
+variable inside the `/etc/asterisk/config.lua` configuration file (see `config.sample.lua`).
+
+> [!WARNING]
+> Don't use "extensions.lua" as the name of the custom script to avoid an error.
+
+Don't forget to reload the pbx_lua module after modifying the scripts:
+
+```bash
+sudo asterisk -x "module reload pbx_lua"
+```
+
+### Sokol 112 trouble
+
+If you use Sokol intercoms, you will have a problem when calling apartment 112, as this device does not allow you to
+specify the SIP number of the apartment. In this case, a call to apartment 112 will result in a call to the SOS
+extension. To fix this, you need to add a custom script that overrides the standard behavior:
+
+```lua
+-- /etc/asterisk/custom/sokol_sos.lua
+extensions["default"]["112"] = function(context, extension)
+    handleOtherCases(context, extension)
+end
+```
+
+```lua
+-- /etc/asterisk/config.lua
+-- ...
+-- ...
+-- ...
+custom = {
+    "sokol_sos"
+}
+```