hook_adapi doesn't receive parameters as documented

Hi!

I wrote my own little module to insert some HTML stuff right befor each ad. Therefore I wanted to use hook_adapi and did similar to what is mentioned in adserve.php regarding operations adserve_init_text and adserve_exit_text. Although my hook gets called, never ever is one of these operations or the current ad node passed to it, so I had to hack around it in adserve.php.