I cant see why that would cause an error like that, for starters:
enclosing those rules inside
<IfModule mod_rewrite.c> and
</IfModule> tells apache NOT to complain if, for some reason, mod_rewrite is not available.
second, I tested exactly that on my own server and got no error back.
youre an old b2evolution user, and you left your phpinfo file up from some posts over on those forums. I took a look.
Despite the fact thats a NIX box, the web server doesnt appear to be Apache. Thats the source of the problme with the code above.
Theres some other people with very similar problems.