You cannot. For this you will have to implement your own version of printParentBreadcrumbs. Those parameters are presumed to be text, not HTML.

we will lose a number of possibilities with this version...
for example, in some news, I put words in bold with [i] [/i] tags, in the title of the news.
it will not be possible either, I suppose.

Not if you use the "print" versions of functions. "get" versions or the object model return raw text.

It is possible to process HTML markup in these functions. But it is expensive (computationally) because the functions would have to parse the string rather than just html encoding it.

We do have a function to parse strings for valid html and encode the rest--that is what is used for news and page content, for instance.

So the choices are:

1. do no encoding--this leaves HTML validation issues
2. encode the string--this means that you cannot pass markup
3. tag_encode the string--this means your gallery slows down.