diff --git a/features/support/env.rb b/features/support/env.rb
index 0f513754..b8b64165 100644
--- a/features/support/env.rb
+++ b/features/support/env.rb
@@ -14,3 +14,6 @@ def run_jekyll(opts = {})
   command << " >> /dev/null 2>&1" if opts[:debug].nil?
   system command
 end
+
+# work around "invalid option: --format" cucumber bug (see #296)
+Test::Unit.run = true