In a letter in Monday's Times, Catriona Malcolm makes some apt observations about what tolerating someone else's beliefs does and doesn't entail:
The traditional dictionary definition of tolerance is "the ability to endure"; that is, the ability to endure someone else's expression of an opinion, even if we find it insulting, demeaning or offensive. This does not preclude criticism of their beliefs but it should preclude censorship of them.
Arguing over the meaning of words may seem to be nit-picking, but in this case it is telling to see that the Encarta dictionary has redefined the word tolerance as "an acceptance of others' beliefs". The ability to actually accept another's viewpoint is very different to enduring it. It is a change to the original meaning and seems quite meaningless; one can understand any belief and accept the right of the individual to hold it, but it would be an extraordinary feat to be able to accept any and every viewpoint without contradicting oneself.