Joomla/SMF Discussbot Links generate an Error 404

[Acirav]

Hi,
I've installed Joomla 1.0.8 and SMF 1.0.7 stable. And both Disucussbots are not working: version 4.1 final isn't working at all. If it's published I get a lot of php errors (most of them in the Subs.php and Load.php from SMF). And with version 4.1b5 there is no error on the mambo frontpage but if you try to klick on the discuss Link ( http://[mywebsite]/[Joomla]/javascript:send_form(1) ) there is an error 404 object not found :/
any ideas?