Siebel to webmethods communication using EAI transports

I am installing Siebel adapter v3.0 on Webmethods Integration 6.0 on Windows 2000 m/c.
While installing the adapter, I selected “Install Adapter & EAI Transports” option since I need webmethods to get notification if any updates happen on Siebel.
The steps for enabling communication between Siebel & Webmethods includes enabling of EAI webmethods transports & for that I need to import some sif file generated & then recompile the Siebel server repository. Has anyone worked on Siebel Adapter 3.0 on Webmethods 6.0 & done the installation too? WHats is the purpose of this SIF file? Is this a mandatory step? I know the other alternative is using Siebel VB scripts but don’t want to opt for this option.
Please advise!
Thanks in advance