How to Alter INITRANS of a Table

Hi

I want to change the initrans of some of my tables.
I tried the alter command but its not working.

Can any of u plz give me an example of how alter inittrans of a table.

Im using Oracle 9i version 1.0.1.1.1 on Windows 2000 server.

alter table X initrans Y

only new blocks will have new initrans though

Thanx Pando.

U r really great.