Enterprise software is the sum of its qualities and parts, just as a good man is. Sure, a good man may have killed a person once in his lifetime, but is he still good in the long run? Is it enough to count against him, for all the right things he's done?
php and perl have a harder time since there's no one company (read authority w/ money, consultants and professionals) saying, "yes, it's good. we provide something and prove it." To some degree, they deliver, to some they don't. Sun does that for java, even if it spins the truth a little, like cross platform compatability. where's my jvm for my c64! ;)
Same w/ ES. Sure perl is enterprise level, but not for the same reason oracle is, different component types. Certainly for not the same reason java is, but they seem to converge a little, w/ the advent of ORMs, XML processing, fast web prototyping and what not. But they don't converge due to the tools involved and their qualities, that can be argued all day long. 'cause it's like pizza toppings. Do we ever agree on that? (Ham and Pinapple ftw!)