Yes I could.. but I didn't want until you asked...
First, get macports, install them...
then get the libmimic library, compile it yourself and install it (maybe using --prefix=/opt/local in the configure step)... you may need to first compile glib2 using macports before trying to compile libmimic.
then using macports, install gstreamer and the port 'gst-plugins-bad'
then once it's all done, you can use the script in amsn's utils directory like this :
/Applications/aMSN.app/Content/Resources/Scripts/utils/cam_to_avi.sh ~/Library/Application\ Supportemail@example.com ~/firstname.lastname@example.org
If it gets too complicated at some point, my best suggestion is : forget about it :p