I get the broken hyperlinks on my Galaxy Tab so I assume it is an issue with the Samsung email app. The problem appears to be that the app does not recognize the "slash" character (and maybe other characters, too) as being part of the link, so it splits it at each slash character. Of course, there are many slash characters in many hyperlinks. I don't know if it does this only on long links, or with any slash after the domain name.
I've never seen this issue on any other device, including other Android devices. This makes email on these Samsung devices pretty much worthless which makes the devices pretty much worthless. On the Galaxy Tab, you can't even copy from the email app so there's no way you can ever use a broken link.
Does anyone know if this has ever been called to the attention of Samsung? Seems like something they'd want to fix. Their engineers must not use their own devices.