diff --git a/stepmania/Docs/Lua.xsd b/stepmania/Docs/Lua.xsd
index 0085dc65b2..2f55aacf37 100644
--- a/stepmania/Docs/Lua.xsd
+++ b/stepmania/Docs/Lua.xsd
@@ -43,6 +43,12 @@
 	</xs:restriction>
 </xs:simpleType>
 
+<xs:simpleType name="FunctionIdentifier">
+	<xs:restriction base="xs:string">
+		<xs:pattern value="[a-zA-Z_][a-zA-Z0-9_]*(\.[a-zA-Z_][a-zA-Z0-9_]*)?" />
+	</xs:restriction>
+</xs:simpleType>
+
 <xs:simpleType name="IdentifierOrTable">
 	<xs:restriction base="xs:string">
 		<xs:pattern value="[a-zA-Z_][a-zA-Z0-9_]*|\{[a-zA-Z_][a-zA-Z0-9_]*\}" />
@@ -123,7 +129,7 @@
 
 <xs:complexType name="Function" mixed="true">
 	<xs:group ref="DocumentationGroup" minOccurs="0" maxOccurs="unbounded" />
-	<xs:attribute name="name" type="Identifier" use="required" />
+	<xs:attribute name="name" type="FunctionIdentifier" use="required" />
 	<xs:attribute name="return" type="IdentifierOrTable" use="optional" />
 	<xs:attribute name="arguments" type="ArgumentList" use="optional" />
 </xs:complexType>