Zoho log in: option to keep the user signed in: not reliable

Zoho log in: option to keep the user signed in: not reliable

I tick the box to keep me signed in.

= Bug =

Every time I begin a new browser session, when next I visit Zoho I find myself logged out.

= Environment =

Safari 3.1.2 (5525.20.1)

Mac OS X 10.5.4.

= Wondering =

Are third party site cookies required?