The upgrade exam and the regular exam have the same requirements, which is why there is not a specific listing only for the upgrade. The differences between the exams are length and concentration - the upgrade is shorter and only concentrates on the Java SE 5.0-specific topics. (Since, in theory, you've passed the areas that deal with prior versions of Java and don't need to be quizzed on them.)
Hope that helps.
Theodore Jonathan Casser
SCJP/SCSNI/SCBCD/SCWCD/SCDJWS/SCMAD/SCEA/MCTS/MCPD... and so many more letters than you can shake a stick at!