Update script fails on Postgresql

The upgrade script includes "ALTER TABLE {video_files} ADD data longtext", but longtext is not a valid datatype for PostgreSQL, so the statement fails. This leaves the DB without a 'data' field, and hence the video module in an unusable state, so I've marked this critical.

I haven't tried any workarounds yet; its likely that manually adding a field of type "text" (PG's unlimited length text datatype) will solve any problems...