Tabulate Area temp files lingering in 10.1 sp1

I'm running a Python script that calls Tabulate Area a few thousand times. After receiving the "Fatal ERROR (INFDEF)" error a few times, I poked around and found that all of the temporary raster (e.g., 't_t908', 't_t_909', etc.) are sitting in the scratch working directory, still with ArcGIS locks and this is causing my problem. Some other important bits of information:

1. This script ran fine with 10.1. The only change (that I know of) was the installation of sp1.
2. I've tried many different scratch workspaces. Even if the temp files are in a FGDB, the script eventually bombs out.

I'd love to hear some ideas. Any fixes besides going away from GRID format for good?