diff --git a/matrix/bar_items.py b/matrix/bar_items.py
index 226b80c..34569e5 100644
--- a/matrix/bar_items.py
+++ b/matrix/bar_items.py
@@ -105,7 +105,9 @@ def matrix_bar_item_buffer_modes(data, item, window, buffer, extra_info):
 
             if (server.client
                     and server.client.room_contains_unverified(room.room_id)):
-                modes.append("⚠️ ")
+                modes.append(
+                    G.CONFIG.look.encryption_warning_sign,
+                )
 
             if not server.connected:
                 modes.append("❌")
diff --git a/matrix/config.py b/matrix/config.py
index b78a536..c612686 100644
--- a/matrix/config.py
+++ b/matrix/config.py
@@ -178,6 +178,10 @@ def logbook_category(value):
     return "all"
 
 
+def eval_cast(string):
+    return W.string_eval_expression(string, {}, {}, {})
+
+
 class WeechatConfig(object):
     def __init__(self, sections):
         self._ptr = W.config_new(
@@ -268,6 +272,8 @@ class ConfigSection(object):
             return bool(W.config_boolean(self._option_ptrs[name]))
 
         def str_getter(self):
+            if cast_func:
+                return cast_func(W.config_string(self._option_ptrs[name]))
             return W.config_string(self._option_ptrs[name])
 
         def str_evaluate_getter(self):
@@ -340,6 +346,17 @@ class MatrixConfig(WeechatConfig):
                 "Typing: ",
                 ("Prefix for the typing notice bar item."),
             ),
+            Option(
+                "encryption_warning_sign",
+                "string",
+                "",
+                0,
+                0,
+                "⚠️ ",
+                ("A sign that is used to signal trust issues in encrypted "
+                 "rooms (note: content is evaluated, see /help eval)"),
+                eval_cast,
+            ),
         ]
 
         network_options = [