It looks like Kingston Technology is serious about their Lifetime Warranty on their products. A little under a week has passed since I had sent them the memory which had gone faulty - and it didn't cost me a penny. They paid for the FedEx shipping both ways. The replacement module looks a little different than the returned and the new modules I had purchased immediately after the failure: They all had identical track layout unlike the replacements. It all seems to work though. The machine has correctly identified the modules and so now it has 4.5G RAM.
On a little side note - I tried to post this message earlier today but the Google Blogger site appeared to be down for maintenance.