The title of the article at law.com "HTC Sues Apple, With Help From Troll" is loaded! There is in no way any friendship or even co-operation between HTC and said patent troll, as implied by the wording of the title.
This reeks of the Apple-fanboi PR guerrilla!
:) I guess this is just HTC getting back at Apple for the latter's patent suit ...
Sadly, recent evidence shows patents being increasingly used to stem (honest) competition than protecting IP