When I build my document, several weird characters appear. Take a look at the picture below:
The most strange thing, is that exactly the same tex file compiles fine on an other computer of mine. I am using TexLive 2011, the same version as on my other computer. A fresh install of TexLive did not solve the problem.
Does any one have a clue about what could be causing this problem? I suspect there is something wrong with my TexLive distribution, not the document. (It also happens for all of my documents, but that could be because they use mostly the same packages (among others fontspec, xltxtra, polyglossia, url and hyperref).