[wp-hackers] Where does is invoked do_enclose?

[Claudio Simeone]

Hi all,

I'm using Wp 2.6.3 with Podcasting plugin to create enclosures with
custom fields so, I want to disable the automatic enclosure creation
when in the post content are posted links to audio and video files.
It happens, in fact, that the post gets an enclosure that is not the
real podcast file, but a simple external link.

So I want to disable that function, but I can't understand where the
do_enclose() function is invoked when a post is saved.
In Codex, and PHP Cross Reference of WP I've found nothing.

In this thread

http://wordpress.org/support/topic/26311?replies=29#post-204574

they say to edit /wp-includes/functions.php, but I don't want to hack
core files if is not necessary.
In the same thread there's also a link to a plugin, but that doesn't
solve the issue. He simply deletes 'enclosure' custom fields that I
need to use with the Podcasting plugin.

Any ideas?

Thanks in advance
Claudio