Arbitrary test failures on Windows

Hi! I was running the PHP test suite multiple times on my Windows machine lately, and everytime I got some different results. Most of the time I get failures for different tests inside ext/standard/tests/file; particularly, fgetcsv_variation*.phpt and fputcsv_variation*.phpt are affected. Having a closer look the failures seem to be caused by race conditions regarding fopen(), fclose(), unlink(), fopen(); apparently, Windows sometimes returns too early from the related API functions. Is that a know problem, or is it only me who's experience this issue? Are there any workarounds? -- Christoph M. Becker