diff --git a/lib/shale/schema/xml_compiler.rb b/lib/shale/schema/xml_compiler.rb
index 5d5194a..a171861 100644
--- a/lib/shale/schema/xml_compiler.rb
+++ b/lib/shale/schema/xml_compiler.rb
@@ -422,7 +422,7 @@ def build_id(node)
       # @api private
       def replace_ns_prefixes(type, namespaces)
         namespaces.each do |prefix, name|
-          type = type.sub(/^#{prefix}/, name)
+          type = type.sub(/^#{prefix}:/, "#{name}:")
         end
 
         if namespaces.key?('xmlns') && !type.include?(':')