Needless warning for "not currently accessible" external disk

[André Pirard]

I created a virtual machine with a sdb.vmdk file pointing to an external disk.
(This is a GREAT feature to prepare a disk to be installed in a PC).

When I start VirtualBox and there's no external disk plugged in, I get a warning.
"One or more virtual hard disks ... are not currently accessible".

It's true (except that it's a real disk), but it's a normal situation.
And routinely ignoring the message now hides abnormal situations.

This warning should be displayed only when the implicated machine is started.
(and it's debatable whether that statement is true for any missing disk)