pressing esc while reading a message in its own window does "Delete & Read Next"

[nmg1]

pressing esc while reading a message in its own window does "Delete & Read Next" action from the Message menu.

this is reproducible every time. i expected the esc key to close the new window.

let me know if you need any further info. this is on mac os x 10.5.1 and mulberry 4.0.8. i haven't tried it on windows yet.

should be easy enough to fix I think. maybe i'll try to dig in to the source myself.