Hi Alessio,
Solution Grove launched two sites this fall on prerelease 5.2 that used "dotlrn-eccomerce" which depends on the APIs from eccomrece and uses some of the pages. Both systems are running postgres 7.4.x.
We committed fixes that added noquote to the adp pages for the eccomerce pages we used but there are probably other adp pages that still have that issue.
We used postgres 7.4.8 and our guess is you may have to fix some queries to use postgres 8.
