Morrison was not too bad at taking punches, but a combination of hard shots usually hurt him badly. Michael Moore springs to mind when I think of glass jaws.
Despite people have already tried to clear Lennox of glass jaw status, Lennox appeared to not like straight shots to the head. Oliver Mcall nocked him down with one, Shannon Briggs sent Lewis wobbling when he hit him with one. Any other kind of shot and Lennox took it fine, it was weird.