diff --git a/Library/Homebrew/utils/gems.rb b/Library/Homebrew/utils/gems.rb
index e6a04b15df..97a68faebb 100644
--- a/Library/Homebrew/utils/gems.rb
+++ b/Library/Homebrew/utils/gems.rb
@@ -63,7 +63,7 @@ module Homebrew
 
     ENV["BUNDLE_GEMFILE"] = "#{ENV["HOMEBREW_LIBRARY"]}/Homebrew/Gemfile"
     @bundle_installed ||= begin
-      bundle_check_output = `#{Gem.bindir}/bundle check`
+      bundle_check_output = `#{Gem.bindir}/bundle check 2>&1`
       bundle_check_failed = !$CHILD_STATUS.exitstatus.zero?
 
       # for some reason sometimes the exit code lies so check the output too.