Charlie Sheen -- Not a Care in the World

6/5/2010 8:52 PM PDT
Charlie Sheen is expected to check in to jail on Monday morning -- but does this look the face of a guy headed to the joint?

Charlie was spotted around LA this afternoon, gassing up his Mercedes and joking with paps.

As we first reported ... if all goes well in court in Aspen on Monday, Sheen will begin his 30-day sentence right on the spot -- with a little work release dinner theater thrown in.