Even though Postgres 7.4.x is officially supported, several upgrade scripts use syntax that only works in Postgres 8.x. and it's impossible to finish the upgrade.
The attached patch fixes those scripts.
Saludos. I�aki.
Author: I�aki Arenaza
Review: Jun Yamog, Martin Langhoff
merged from MOODLE_16_STABLE
The database checks/upgrades are now done on the main
admin page like the other modules.
The database files are now standard format .sql and .php files
PostgreSQL support was added - BUT HAS NOT BEEN TESTED YET!!