ZAP 2.4.0 includes:
- Attack Mode
- Advanced Fuzzing
- Scan Policies
- Scan Dialogs with Advanced Options
- Hiding Unused Tabs
- New Add-ons
- New Scan Rules
- Changed Scan Rules
- More User Interface Changes
- Extended API Support
- Internationalized Help Add-ons
For more details see http://owasp.blogspot.co.uk/2015/04/owasp-zap-240.html