How to index filenames?

[mordormx]

Hi there, i have phpdig working so cool,
I have an script that checks the new files uploaded for the users, i generate a list and i do the spider on the list of files, but some of this files are autocad for example, and as i know theres no a way to index that files, jst like .doc or .xls, so i would like to index the filenames, so the users could find using keywords and filenames too.
Theres a way to do this in phpdig?

Thanks in advance!