i have ever met the same problem, but i solved it by another way. You can load the expored PDF file to Adobe Acrobat Pro for editing, It would be OK. From my experience, I like to use Word to edit my contents and after finishing that work, I would save Word as PDF using Cute PDF Writer or Office 2007 add-in. If I found some mistakes need to modified in the PDF format, I would edit the contents in the original word process and then save it as PDF again, and again. Actually I don't like to use Acrobat for creating ebook. It is not easy to learn well. I just use it to edit some details when I don't want to save all again. Of course, different guy has his own way. There is another way, known as the article How to edit PDF text , you would take it for reference.
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