arcpy.Buffer_analysis() fails sporadically

Hi Folks,

I'm experiencing a frustrating and inconsistent issue when I try to generate a buffer around a polygon. I'm using arc 10.1.

Over the course of my program, I call:

(where `in_shapefile` and `out_shapefile` are of course paths to shapefiles) on a large number of polygons. Usually this works fine, but occasionally the out_shapefile ends up empty (it is created, but contains no polygons, and the attribute table is empty). This behaviour doesn't occur in any consistent way I can figure out. I can re-run my program and it will fail on a polygon that it succeeded on last time, or sometimes the whole program will run successfully (over the same data).

I can take the in_shapefile that failed and run it through a test program that calls an identical buffer_analysis command on it 1000 times without failing. I've also tried running the same code on a machine with arc 10.0, and haven't seen this issue.

Does anyone have any suggestions? Have I found an arcpy bug?

Thanks in advance,

Tom