Zoho Mail Page Caching Bug

Zoho Mail Page Caching Bug

Steps to Reproduce:

1) Logon to Zoho Mail using (G) -- Google Mail Account
2) Use Zoho Mail normally.
3) In the same window goto Gmail.com
4) Logout of Google Mail and Google Accounts completely
5) Now use Browser Back button and Navigate to Zoho Mail. It still remains signed on!!!