Jagged text and graphics for scanned PDF documents in Ubuntu

I download a lot of scanned articles in my work. These are usually in PDF format, and the default viewer for PDF files in Ubuntu is Evince. However, for the scanned articles, the text is really jagged and hard to read. It seems that this is due to "missing anti-aliasing", and judging from this forum thread, several other users are having the same problem. A fix seems to be on its way, but while I'm waiting, I've installed Okular (a document reader for the KDE desktop), which renders the scanned text beautifully.