Bug happens here as well, with 1.96 and 1.98. Seems to occur when the sphere is on the same axis as an edge of the box.
It should be fixed. Ellipsoid to box collisions were always a bit flaky as elipsoids were primarily introduced for use in polygon collisions, but this seems to pretty much invalidate using sphere to box collisions as well.
Strange it has not been noticed before. Ellipsoid collisions were added back at 1.81 when one might assume the problem was introduced, however I note from versions.txt that some additional collision work to tighten things up was done at 1.88 which coincides with your findings.
It would be really hideous if it works ok on some systems and not on others.
It should be fixed. Ellipsoid to box collisions were always a bit flaky as elipsoids were primarily introduced for use in polygon collisions, but this seems to pretty much invalidate using sphere to box collisions as well.
Strange it has not been noticed before. Ellipsoid collisions were added back at 1.81 when one might assume the problem was introduced, however I note from versions.txt that some additional collision work to tighten things up was done at 1.88 which coincides with your findings.
It would be really hideous if it works ok on some systems and not on others.