diff --git a/dns/bind/src/opnsense/mvc/app/models/OPNsense/Bind/Acl.xml b/dns/bind/src/opnsense/mvc/app/models/OPNsense/Bind/Acl.xml
index 6abff3a73..474a0a0df 100644
--- a/dns/bind/src/opnsense/mvc/app/models/OPNsense/Bind/Acl.xml
+++ b/dns/bind/src/opnsense/mvc/app/models/OPNsense/Bind/Acl.xml
@@ -13,7 +13,7 @@
                     <default></default>
                     <Required>Y</Required>
                     <mask>/^(?!any$|localhost$|localnets$|none$)[0-9a-zA-Z_\-]{1,32}$/u</mask>
-                    <ValidationMessage>Should be a string between 1 and 32 characters. Allowed characters are 0-9a-zA-Z_-. Built-in ACL names must not be used: any, localhost, localnets, none.</ValidationMessage>
+                    <ValidationMessage>Should be a string between 1 and 32 characters. Allowed characters are 0-9, a-z, A-Z, _ and -. Built-in ACL names must not be used: any, localhost, localnets, none.</ValidationMessage>
                 </name>
                 <networks type="NetworkField">
                     <default></default>