Issues with having underscore in domain name

I have come across wierd hair scratching problems and this is one of them. Turns out, if there is an underscore in your domain/sub domain name, IE stops saving cookies. Which i have already mentioned in my earlier post title ‘IE Why? Why?‘.

Now another issue that I have noticed with underscore in domain is that PayPal will not accept this url as a valid url. So if your site has PayPal processing then it will error out.

All the fun with having underscore in domain names.

IE why? why?

Today, I came to know about another issue with IE browser. Apparently, IE browser does not allow cookies from sub domains that do not follow URI RFC. I wasted a few hours of my time trying to figure out why cookies were not working on my test site. Turns out this was the case.
IE why? why do you have to suck?