How-To-Repeat:

Using MySQL 4.0.1 on Windows 2000, I open 2 command shells and do "mysql test" in each.

Then in shell 1 I do:

create table Z (i int);

Then in shell 2 I do:

select * from Z;

Then in shell 1 I do:

rename table Z to Z2;

which results in:

ERROR 7: Error on rename of '.\test\Z.MYI' to '.\test\Z2.MYI' (Errcode: 13)