If it's container managed transactions on EJBs then you can use the @org.jboss.ejb3.annotation.TransactionTimeout annotation which takes a value in seconds.
Or you specify a different unit like
@TransactionTimeout(value = 1, unit = TimeUnit.DAYS)
Guys, thanks, boyth answers are correct.
another question- do we have in JBoss something like Application scope in Servlets- something that I can wrote Application[key]=value- and all Ejbs in the same ear could see it. I know about JBoss Cache but is there something more simple?