OK, so you can edit PDF documents if you own a full copy of Adobe Acrobat. I didn't imagine that a problem like this would warrant spending a lot of money, for something that should be simple to fix at source. Just because you can edit a PDF, it doesn't mean you should, and why should you, if you can fix the source and re-create the PDF?
(This is assuming that the OP's using a PDF Creator plugin, like Foxit, or the free one from Microsoft for Office 2007. )