Nagini and the Invisibililty Cloak - thoughts?

[doppioprego]

No: HPFGUIDX 172611

I have spent the whole morning catching up on the posts and nowhere can 
I see mentioned Nagini's ability to see through the cloak.

In Godric's Hollow, Nagini (as Bathilda) was able to see, recognise and 
beckon Harry to come into the house, despite the fact he and Hermione 
were under the cloak AND disguised as a middle-aged couple. In the 
Shrieking Shack during the Voldemort/Snape showdown she is shown is 
floating around in the bubble whilst Snape repeatedly asks Voldy 
to 'let me bring you the boy'. Why would Nagini not have spotted Harry 
hiding under the cloak and told Voldy of this? Would have spared an 
awful lot of time and magical effort in destroying the Hogwarts castle 
to root him out.

Forgive me if I am remembering inaccurately (I don't have the book to 
hand and have only read it the once). I'd be interested to hear your 
views.

Dee, a long-time lurker but first time poster