Well, you wrote
When i setup my integration tests a while back i took a SQL dump from production db and converted that to HSQL (DDL & inserts).
so automate this process - build some scripts or program which does what you did with as few manual steps as possible, then you can repeat the process of updating your test database much easier and as often as needed.
Side note to the commenters: Having the schema change first in production, and updating the OP's application afterwards can make perfectly sense if the application is not a production-critical part of an enterprise system. For example, an application which is used to make some data analysis on a production database at the end of a defined period like a quarter or a year. Under given time constraints, it does not make sense to stop the development/deployment of production critical apps, and wait until every minor important analysis tool was tested against the new schema.
(Don't get me wrong, I hope for your production critical apps there is something like a test database, and your colleagues test those applications first in that environment before deploying into production).