No, I am not asking if I can use one.
But the question do we simulate a static variable, if at all I need to?

also, suppose my session bean uses some plain old java object to a thing or two, for ex:
public sessionBeanMethod() throws EJBException {
   Foo f = new Foo();

Suppose doSomething() inturn incrments some static variable with in Class Foo - did we go against EJB Spec?