W300i and HBH-608 Headset

Hi, here's my problem. I just bought a HBH-608 bluetooth headset for my W300i. I was able to connect it to my phone but when I click on the button to make a call, a message appear to tell the name of the person I want to call, but when I said the name nothing happend. I've tried with the one that came with the phone and it worked, so is it possible that it's the microphone thst is broken?

Thanks