This is not a direct answer to your question, but i suppose you want Samba to be installed in first place, no matter how.
Go to
IBMs Linux toolbox for AIX and download the two (three if you need the client too) packages in RPM format you will find there: "samba-client 2.2.7", "samba-common 2.2.7" and "samba 2.2.7".
Save the files to a directory and install with "rpm -i *".
As IBM is the manufacturer of your OS you have to trust them anyways.
I hope this helps.
bakunin