Alternate email client?

[bgsmith01]

Is it possible to use an alternate email client with Mozilla (0.92 right 
now)?  For better or worse I work for an agency that uses Lotus Notes and 
Domino as email client and mail server. It is easy to reconfigure MS IE 
5.x to pop open a new mail window in Notes when clicking on a mailto: 
link. There are instructions on the Iris web site for doing the same with 
Netscape 4.x (altering a setting in prefs.js). Can something similar be 
done in Mozilla?

Thanks,

Brad