tl;dr:  
Almost; in the Trás-os-Montes dialect they pronounce it /ʒ/.

# Long answer

The s at end of a sylable is pronounced /ʃ/ in most of Portugal, and that is the correct pronunciation.

But in the [dialeto transmontano](https://pt.wikipedia.org/wiki/Dialeto_transmontano) (interior north of Portugal)  the /ʃ/ is pronouced **/ʒ/**, like the j in *gajo*.  
With this accent, Trás-os-Montes would sound like "Traj-oj-Montej".  
The Wikipedia page links to a [sound sample](http://cvc.instituto-camoes.pt/hlp/geografia/som4.html), which I suggest you listen to.

These thick accents are becoming less common, in my opinion due to the uniformization of language and the influence of TV's centralized accent.

For more information, read the WikiPedia page on [dialects of Portuguese](https://pt.wikipedia.org/wiki/Dialetos_da_l%C3%ADngua_portuguesa).  
The subpages are not very organized, but these articles are very interesting.