Just a thought, but would it not be possible to add a trigger written in python that makes a connection to another database and does what it needs to? I have not done this, but if it is possible it should solve your problem and one that I have. It should allow updates and selects.
I am sure the docs will tell you how to do perl or python based triggers and if you can use external modules in them...if you can, it would be a rather straight forward python app that accesses the GIS tables using a DB connector (postgres or mysql or what ever).
Since I have not read much (more or less nothing) about triggers I could be way off base and entirely wrong.
Thanks,
Kobus
