I think this is a philosophical/logical paradox.
If you decide not to tolerate 'something' this will make you intolerant (or not 100% tolerant). In this case of yours, you're intolerant when it comes to intolerance. So, to solve the paradox, you have to predefine the list of things that you can't tolerate. So, instead of saying "I'm a tolerant person," one should say "I'm a tolerant person except when it comes to ..." I think that's the only way for establishing credibility as being 'conditionally' tolerant, but it also makes your tolerance subjective (since other people might come up with their own lists of exceptions). This means that your flavor of tolerance will be difficult to scale and be applied to the large masses.Things get even worse when you try to define the boundaries of 'intolerance' you can't tolerate. This all boils down to how challenging it is to establish a 'tolerant' society.
A good example of the paradox is freedom of press in some countries where the government can tolerate any article or opinion except when it comes to ridiculing religion.
This reminds me of the slogan: Fight For Peace.