Droid X: Bootloader while charging by USB ??

I've already seen a couple mentions of this on forums, in somewhat unrelated threads so I'm wondering how common it is. When I charge my Droid X by USB and it's powered off, it goes to bootloader and I cannot turn it on again until I unplug it. I called Verizon and they are sending a new phone when they come in and say they have never heard of it - I have also had mine spontaneously reboot a couple of times too (? related). The posters I've seen, spoke of it as if it was normal, but I know my husband's doesn't do this. So anyone else - and if so, any other issues too?