Forum OpenACS Q&A: Re: upgrade from PG 7.2.4 to 8.3.4 and OACS 3.2.5 to 5.1

the PG team doesn't make backwards compatibility a design priority.  Just get used to stuff breaking when you upgrade. :-|

Doesn't 5.1 work on PG 7.4 though?  If so you should save yourself some hassle and upgrade to the latest.