Counter gone hay-wired?

I just changed my visitor count to unique visitor counter 2 days ago. Yesterday at my aunt's house (using Streamyx broadband) the count was genuine, i.e. when I refresh the page the visitor count doesn't increase because unique visitor count is suppose to count one person per day basis. So even if one refresh the page many times it will only count the visit as once. If the person visit again the next day only it will recount it as second visit and this thus add up to the global visitor count.

But today when I refresh this blog in the lab, the visitor count increased with every click I made on the refresh button. I'm not sure what went wrong because the code should be exactly the same since I didn't touch the code part last night. The code won't change over the night won't it? Or maybe it's the type of the connection system here in the lab is different thus making the counter unable to recognise the visitor identity? lol.

Just wondering why so weird one cuz I want to keep tract of the number of visitor per day. =)