This is not a Tomcat error. It's improperly-coded JSF EL. It can be expected to fail regardless of what J2EE server hosts it.
EL is not supposed to be a "programming language" to begin with, so writing EL as if it was is a bad practice even when done in valid ways. And, as I often point out, putting logic in View definitions is a violation of the MVC Separation of Concerns concept in any event.
Customer surveys are for companies who didn't pay proper attention to begin with.