Redirect all traffic except one specific directory?

This is a multi-part message in MIME format.

------=_NextPart_000_0008_01C7B59B.B7FD5620
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

I want to redirect *all* traffic to http://mysite.com to =
http://destination.com, except for one specific directory.

Here is my .htaccess file:

RewriteEngine on
RewriteCond $1 !^SomeDirectory
RewriteRule (.*) http://destination.com/$1 [L]

So if I type in http://mysite.com/SomeDirectory it works fine, taking me =
to that directory. And if I type in http://mysite.com it takes me to =
http://destination.com.

But if I type in *anything* else, whether it is an actual directory or =
file, or whether it is a typo, it takes me to an error page on the =
destination site. For example, http://mysite.com/TypoError takes me to =
http://destination.com/TypoError with a "404 File Not Found Error".

Is there a way to have it so *anything* other than =
http://mysite.com/SomeDirectory will get redirected to =
http://destination.com?
------=_NextPart_000_0008_01C7B59B.B7FD5620
Content-Type: text/html;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable



charset=3Diso-8859-1">