One of the issues is that there doesn't seem to be a standard,
automatic way of porting any given package from Oracle to
PostgreSQL. One important issue, as you point out Roberto, is
default values for parameters. Some of the ACS packages use
these default parameters quite often. Don and I discussed the
idea of using function overloading to represent the most
common forms of these function calls, given the way they are
used in ACS. Of course, this is not a complete solution.
So, this is going to be a hard section for you to write: it's a very
much a porting effort that requires examining the *use* made of
these function calls.