KKrtz wrote:
physical to physical have the same problems like vm's...
That is interesting of course, since that means it is just not only a logical problem inside the vSphere hosts, but something that really happens on your physical network.
Do you have access to the 2960 from CLI / Telnet / SSH? Could you look at the logs if something obvious does happen when you do the vMotion? Look for any Spanning Tree events, which should not happen, but if the host NIC for some reason is overloaded and disconnected then it might trigger a STP recalculation.