Modifying the Server Message, input field and DB entry?

[Lost-Ninja]

I have already changed the actual web page so that the text box that takes the '%%SERVERWELCOMEMESSAGE%%' is a multiline text box, so that longer messages can be read. I noted that the max entry of the old box was 255 characters which led me to think that the storage with the DB is a varchar field. How would I change that if it is the case to a larger field size?

Also I note that the software turns a plain url into a clickable link are there any other things that are interpreted? Allowing for instance line breaks or formatting?

I checked the FAQ and did a quick search but couldn't see any answers for the above, apologies if I have completely missed something. :(