Principal bundles over a curve in positive characteristic, II

This is a postscript to our earlier paper [Bull. Sci. Math. 128 (2004) 761-773]. In [Bull. Sci. Math. 128 (2004) 761-773] a criterion was given for a principal bundle over a curve to be strongly semistable. This led to a conjectural criterion to characterize semistable principal bundles. Here we construct examples to show that this generalization of the criterion fails.