Small question Temp Folder

[Drocona]

Hello readers,

I've been using RoundCube for a while now on my webhosting package, however the Temp folder just keeps growing and growing and never seems to be cleared (not really TEMPORARY is it?)

Just wondering when is it cleared? It almost makes my hit the storage limit.
Can I safely clean it without people losing attachments etc?
Is there a configuration variable somewhere where I can set when to clean the temp folder?

Tried the search, but came up with nothing.

Thanks for your time,

Matts