WordPress MU

I'm just finished writing a plugin that will allow you to use one line of php code that will call a category cloud for either the whole wordpress mu site, or your individual site.

In my plugin, when ever I use

bloginfo('url')."/category"
or
bloginfo('wpurl')."/category"

and no matter how I use it, unless it is commented is causes me to get this error when I activate or deactivate the plugin:

Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/wpmu/wp-includes/general-template.php:70) in /var/www/html/wpmu/wp-includes/pluggable.php on line 281

If I try to print bloginfo('wpurl')."/category" in another place like my sidebar, i get no error.

Right now it works to just manually enter the url of the site, but that wouldn't work if I wanted individual users of each blog to be able to just call the cloud where ever they want.

please help!

Are you trying to actually print it? Does get_setting do the same thing?

Hi, I just got back to the office. If I use get_setting('url') or get_setting('wpurl') to set the current blogs url to a string variable I just get an error that says that get_setting is not a function. I can't find information on this function, am I missing some syntax?

Nevermind, I found it here
it's get_settings, though
http://codex.wordpress.org/Function_Reference/get_settings

I really appreciate your help!

we're waiting for your plugin ;-)