Information Schema - Can the views be applied to older versions of PostgreSQL

My name is Mike Griffin and we are adding PostgreSQL support to our
product, MyGeneration. MyGeneration pulls meta-data from DBMS systems to
generate business objects and stored procedures and such.

We are using the .NET managed provider Npgsql.dll. We typically get meta
data from OleDb providers and they provide good meta, however, there are
none for PostgreSQL that support the meta data services, so we're hitting
system tables.  I'm very familiar with the INFORMATION SCHEMA views as
Microsoft SQL server and other databases support them, as does PostgreSQL
7.4 and up, however, if we only support 7.4 and up we'll be losing out on
most of the installed PostgreSQL user base.

So now I'm writing monster queries against system tables, I mean monster
queries. It's brutal.

So here's my question:

Can I take the INFORMATION SCHEMA views from 7.4 and install them in older
versions of PostgreSQL, if so, how far back can they work?

Mike Griffin
MyGeneration Software
http://www.mygenerationsoftware.com