Too few characters supported for the original url

When it happens: When using modules which put in the url the original name of page or a taxonomy term etc. eg.: in a Greek article (index) page we have to cope with a url such as this : http://examplesite.com/article/%25CE%25B5%25CF%2580%25CE%25B9%25CE%25BA%...

What happens: If we try to get a short url alias for the url above, only the first 20 or so characters will be stored, and thus the url alias will be broken

What needs to be done: Increase the length of the original path