I'm sorry, I wasn't paying enough attention - like you said, the JavaScript needs to go in a template and that part you posted adds to the footer.
Try this:
Code:
<phpcode><![CDATA[$js = "<script type=\"text/javascript\">
var _SKYAUTH = {
loginUrl:'http://www.weltmuzik.com/forum/login.php?u={$vbulletin->userinfo[userid]}',
memberNick:'{$vbulletin->userinfo[username]}',
memberId:'{$vbulletin->userinfo[userid]}',
profileUrl:'http://www.weltmuzik.com/forum/member.php?u={$vbulletin->userinfo[userid]}',
photoUrl:'http://www.weltmuzik.com/forum/image.php?u={$vbulletin->userinfo[userid]}'
};</script>";
$vbulletin->templatecache['footer'] = str_replace('$ad_location[ad_footer_end]', '$skysa_toolbar $js $ad_location[ad_footer_end]', $vbulletin->templatecache['footer']);]]></phpcode>