diff --git a/activerecord-oracle_enhanced-adapter.gemspec b/activerecord-oracle_enhanced-adapter.gemspec
index 023637755..3dbafdaec 100644
--- a/activerecord-oracle_enhanced-adapter.gemspec
+++ b/activerecord-oracle_enhanced-adapter.gemspec
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "rake"
+
 version = File.read(File.expand_path("../VERSION", __FILE__)).strip
 
 Gem::Specification.new do |s|
@@ -17,7 +19,7 @@ This adapter is superset of original ActiveRecord Oracle adapter.
   s.extra_rdoc_files = [
     "README.md"
   ]
-  s.files = Dir["History.md", "License.txt", "README.md", "VERSION", "lib/**/*"]
+  s.files = FileList["History.md", "License.txt", "README.md", "VERSION", "lib/**/*"].exclude("lib/ojdbc*.jar")
   s.homepage = "http://github.com/rsim/oracle-enhanced"
   s.require_paths = ["lib"]
   s.summary = "Oracle enhanced adapter for ActiveRecord"