wpmu dev seo

HI, I am running wordpress MU 2.7 (I haven't been able to successfully upgrade to 3.1.1 so I have been stuck on wordpress mu 2.7).

I am looking for a way to convert all existing (and future) occurrence of a word or a phrase into a hyperlink across all blogs. I think WPMU DEV SEO will be able to do this, but it doesn't work with my old wpmu 2.7.

Is there an older version of WPMU DEV SEO that will work, or perhaps another plugin that will do the word/phrase conversion for me?

Otherwise, I may have to write a script to go through all blogs and replace it from the database..
thanks.