DT_WSTR is a string. You can check out a list of all the Integration Service types here:
I have not read the book and you didn't really explain what the "bug" was so I can't even begin to fathom a response for you. By and large the community here does the best it can to answer peoples questions (none of us are paid to be here) but, sometimes, questions simply won't get answered because noone may know the exact answer to your question.
Also, so that Wrox can correct these problems in future editions, post the problems you are having on the books errata page. (The errata for this particular book can be found here: http://www.wrox.com/WileyCDA/WroxTit...ew_errata.html
If you can be more specific with the problem yuo are having i can try to help you out.
Read this if you want to know how to get a correct reply for your question:
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