Always include a new line at the end of your .htaccess document.
It is not important until you change something in Cpanel.
I had a very hard time, trying to figure out why I got an internal server error (was to stupid to read the error log, but anyway), but in the end I figured out, that it happened because I changed some Handlers in the Cpanel, which led to the last line of my .htaccess looking like this:
magic_quotes_runtime offAddHandler php php4or something like that..
It took me ages to figure out what was wrong, because I didn't remember screwing anything up. So be careful regarding this behaviour.