Right now, there is no book available for that exam. Three of the developers of the new exam (myself, Bert Bates, and Bryan Basham) are working on the 1.4 exam book now, but it will not be ready until May.
For now, besides the specs, there is PRO
JSP (APress, I think), Marty Hall's new edition of Core
Servlets, and there's a book with a picture of a yard gnome on the front (Servlets and JavaServerP Pages by Jayson Falkner and Kevin Jones) I think are pretty good
The older SCWCD book by Deshmukh and Malavia is an excellent book as well, even though it is not up to date for this exam. But I still recommend it. It no longer matches the new exam objectives all that well, and it's mock questions are VERY well matched to the older exam, but do not reflect the nature of a lot of the new exam questions (there's more code, and less knowledge memorization on the upcoming exam than in the older/current version of the exam). Still, it's a great book and if you can get your hands on it, I recommend it in addition to the specs and probably one other book that covers the new stuff.
None of these books covers everything you need for the exam, though, so you really must have the specs as well. Unlike
EJB, and perhaps the J2ME stuff, I do not personally believe that the specs are enough for this exam. Although with enough experimentation you *could* figure everything out, but unless you are already expert in these technologies, I recommend both a book or two AND the specs.
cheers and good luck...
-Kathy