4.0.20 -> 4.1.2 Problem with tmp directory growing up

[track1]

after upgrading to from 4.0.20 to 4.1.2, /tmp/ directory begins to grow (1gb), but do not get to show any files that occupy that space. Restarting litespeed returns to be free space and starts to grow again.

Any idea?

Cache is activated but cache files only takes 50-60mb and there is a cron task that deletes.

With 4.0.20 /tmp/ dir have about 90% free space and doesn't go up.