a question regarding the other Portishead...

remember when the albums Pearl and Aliens were released and everyone was like "hachie machie, a new Portishead album is coming out," but it turned out that it was by another band called Portishead?
has anyone actually heard this band?
i downloaded some of their work, their album Pearl turned out to be Mandalay's Empathy. this could be a mislabelling of sound files.
the songs on Pearl are the same as Empathy.
my question is, is Aliens a Mandalay album as well? or is this all a mislabelling among the cyberspace community? or is it a case where a band is known by one name in one country, and has to change it in others (like the Charlatans)?
thank you.