Sure - lockup the mirror.  Use a squeeze-bulb with the body opening
facing down - you want anything dislodged to fall out of the camera,
not migrate into it.  Never use canned "air," because if any of the
chilled fluid hits the sensor, it will likely damage it.  Never touch
the sensor, and don't use a lens dust brush.

Look here please http://www.pbase.com/copperhill/ccd_cleaning
I did it already a few times without any problem

Good lock,
Harry