we've got a similar problem with a T-DNA insertion line we obtained from
Syngenta. This line is in a Col-0 background, and when we tried to
complement the mutation, we discovered, that all of the plants were
already Kanamycin resistant...
We've no explanation for this, but I'm sure, that when you repeat the
experiment with new (i.e. newly bought) Ler wild-type, it will be
Menzinger Str. 67