Our site has a lovely name "Reppu: Lahden ammattikorkeakoulun tiedotus- ja verkko-opetusympäristö" which is 71 characters (ä and ö make two each!). This doesn't work as the organizationName variable of the Distinguished Name parameter of the function openssl_csr_new().
The obvious workaround is to make the name to be shorter, but as there is no warning about this anywhere it might be hard to spot from a production site that has notices turned off.