I am the only developer working on a web application which is nearing to its end. Now we are looking into making it Live in maybe a couple of months time. 

This is a web application for a non IT company. Though they have their own internal IT team, they have asked me on what will be the hardware requirements for the live servers eg. RAM, 32 bit or 64 bit.

Shouldn't the internal IT team be doing this or since I am the only person working on the project is it my resposiblity to let them know of the any specific hardware requirements which may impact the performance of the project? 

The reason I am asking this question is that, I have not done this before. All the times I used to be given a server and asked to deploy apps on it. I never used to worry about the server configuration, etc. 


  Though they have their own internal IT team, they have asked me on
  what will be the hardware requirements for the live servers eg. RAM,
  32 bit or 64 bit.


Perhaps they figure that as the developer, you have more insight into the app's requirements than they do. You've presumably been running the application and know how much memory it requires under different loads.

From the IT department's point of view, they're happy to supply whatever your application needs. They could probably figure out what the application requires through trial and error, or they could ask the one guy in the company who's likely to have some insight into the application's behavior for his opinion.

It's not uncommon for developers to be asked to do things that aren't strictly in their job description. You might have to write some documentation, even though there's a technical writer on staff. You might need to participate in the testing process even though there's a QA department. Or you might be asked to help write a proposal even though there's a business analyst on the project. This is normal -- you're part of a team, and your main concern should be helping the team succeed. It's also good for you since it expands your experience and helps you understand what the other team members do, and it's good for the company since it spreads knowledge around.
