After hours of frustrated attempts, I finally managed to get a working Squeak development image with both Seaside and Glorp loaded–with invaluable help from Ramon Leon of On Smalltalk fame, who found out what I was doing wrong. The image is built upon the full 3.9 Squeak image, and was tested on both Windows and Linux.
It took me a few tries to get Glorp loaded into the image since the port was created for the 3.8 release, but it seems to be working well now. I had to patch a couple of methods, and now most of the tests pass (only three out of seven hundred are failing now, and I believe one of them is too version specific and should be rewritten anyway). This version requires PostgreSQL 8.2 with plaintext authentication enabled.
If you are interested in giving Smalltalk a try, Squeak is a good way to start. This development image requires only the stable release, which can be easily found on the Squeak site, a nd will work on any of the support platforms.