s.in.stf1 source code

Hello Grass Users:

Where is "s.in.stf1" source code?

We need it to integrate Tiger/Line Maps with STF1 Census Data. I have
compiled Grass4.1 on our IBM RS/6000 and couldn't find "s.in.stf1" code.

Any Ideas? to where I can find the source code or binary file complied
on RS/6000...

--Ravi Kutumbaka.