在IIS 6.0中使用SSLv3

I recently got a notification from a McAfee service (what used to be called HackerSafe) that my website is using SSLv2 and it should be using SSLv3. I don't know anything about the versions of SSL. My site is using IIS 6.0, is there a setting somewhere to turn on SSLv3 or do I need to install something to make this happen? Also, is there any drawbacks to only using SSLv3? Are there browsers that can only use v2?I recently got a notification from a McAfee ser