I am running FC6 with the OO version 2.0.4 that comes with it. I never saw my current problem with previous versions of FC and OO.
I often create writer *.odt documents with inserted formula objects (insert > object > formula). Several times now this problem has come up. The formula is correct on the screen in the document; the formula is correct in the page preview. However, it does not print correctly. The problem usually consists of two letters in the formula printed on top of each other. However, this only happens with one or two formulas, not every formula in the document.
The printer driver used also comes with FC6, although it was the same driver in earlier versions of FC and never produced any problems. It is supplied by HP and is called hpijs. So I doubt the problem is the driver.