PG 8.3 is missing other functions. Because current Ubuntu installs 8.4, supporting this version is already a good step.
This drops the need to handle the version number in any file and simplifies the test suite setup.
Note that for some reason the SumTable benchmark has gone more than twice faster than the previous run. Don't know what is the difference: probably the first run was with PostgreSQL from package manager and tne second with the one compiled myself. Will try to investigate more.