I agree with Dwiht, I have always seen these messages when any of these 
processess are running at
the same time and these are Exp Inv and Space Rec  Or Exp Inv and Delete fi. 
But the message has had no
effect on the server so far........ I usually cancel the Exp Inv and then run 
it at a time when the server is
more available - you can also schedule your expire inventory through Admin 
command schedule.

Hope this helps.

Mansoor Bajwa
Canadian Pacific Railway