How to edit eps file to change fonts?

I have some eps files that I'm using as figures in a paper, and I'd like to change the fonts used. I need to convert all "Type-3" fonts to "Type-1" fonts. Is there a way I can edit the eps files directly and change the fonts used?

Sorry Christoph I saw your comment almost 2 years too late, but for future Googlers I've come across a couple of solutions since I asked this question: 1) You can use Ghostscript to convert fonts in PDF figures directly, 2) on a Mac, you can "save to PDF" in Preview on the entire document, which will convert all fonts to Type-1 with the appropriate settings.