search: intended behavior?

[Jon Daley]

	Just wanted to make sure that roundcube is doing the expected 
thing with putting the searches in the session data in the database, and 
not erasing the data (ever, I think?) but just appending new searches, so 
the session data gets larger and larger?
	I presume this is for caching, but it surprised me when looking 
through the mysql logs to have pages of messages #s in the session data.