[phpOpenTracker-general] trouble getting phpOpenTracker running via webbug

hello all,

i am trying to install phpOpenTracker on my site, using the webbug to 
initiate it, since much of our website is perl- rather than php-based.

i am encountering this error when i load a page containing the bugs 
suggested in the examples/webbug/index.htm file:

    Sep  9 16:08:32 www httpd: PHP Warning:  session_register(): Cannot
    send session cookie - headers already sent by (output started at
    /home/medzilla/httpd/html/image.php:31) in
    /usr/local/lib/php/phpOpenTracker/Container.php on line 67
    Sep  9 16:08:32 www httpd: PHP Warning:  session_register(): Cannot
    send session cache limiter - headers already sent (output started at
    /home/medzilla/httpd/html/image.php:31) in
    /usr/local/lib/php/phpOpenTracker/Container.php on line 67

i've tried to debug this, but setting the debug level to 2 sends no 
output.  i've searched the web for people with similar problems but 
haven't found any clues.

perhaps i have it installed incorrectly?  i'm not sure how the 
OpenTracker system would be able to send headers at all, since the file 
the webbug is included in has already sent out headers?

any help would be greatly appreciated.  i speak some german, but but 
english is my primary language.

thanks,

jB