WordPress MU

The full error can be found at the bottom of http://www.themostlyhonesttruth.com. It says
Warning: constant() [function.constant]: Couldn't find constant yes in /home/clark544/public_html/wp-admin/includes/mu.php on line 718 any ideas what this could be?

I can't see it on the page at all.

718 in mu.php is

if( constant( VHOST ) ) {

So what does the define line look like in wp-config.php. It should look something like:

define('VHOST', 'no');

Maybe it's because I'm logged into admin.

Mine says:

define('VHOST', 'yes');

It's the same syntax, but what does VHOST mean? I assume it's virtual host. But what exactly is that?

In some of my installs this error in backend appeared when Settings -> General did not have a Blog Title or if it had some funky characters in Blog Title.

We noticed in some upgrade cases vhost returned a null result when it shoudl be yes or no.

yes means subdomains, no means subfolders. So check in the config file.

I'm using the domain mapping plugin. I believe I need to have it set to yes.

As I was playing around, you'll notice that some of my links such as categories point to bleepgate.com instead of themostlyhonesttruth.com. Could this be part of the problem? Why would it do this?

I'm going to do a complete reinstall and see what happens

I'm seeing this error.

Should line 718 of mu.php be:

if( constant( 'VHOST' ) ) {

instead of

if( constant ( VHOST ) ) {

(ie: quotes missing)

?

A quick test seems to suggest this is right, but I know nothing of php.

The same error seems to be in includes/wpmu-functions.php line 2117, quotes are missing. It should read

...
if( constant( 'VHOST' ) ) {
$blog->blogname = $blog->domain;
} else {
$blog->blogname = $blog->path;
}

I think this has been fixed in the 2.7.1 branch.