You can manually import your IE Favorites but you have to first use Internet Explorer to export the Favorites to a file, then use the Mozilla Suite SeaMonkey or Firefox Bookmarks Manager to import it.

To export your IE Favorites to a file

   Open Internet Explorer
   Press the "Alt" key to show the IE menu toolbar, if the menu bar is hidden (File, Edit, View, Favorites, Tools, and Help menu items).
   In the IE menu bar, go to "File -> Import and Export..."
   Follow the prompts to export your IE favorites to a file, which will be named "bookmark.htm" by default.
   After you've finished exporting your IE Favorites to a file, use the Mozilla Suite/SeaMonkey or Firefox Bookmarks Manager and import the file. 

Note: Specific steps to export your IE Favorites to a file will depend on your IE version. Check Internet Explorer Help (from the IE Help menu) or read this article.

http://kb.mozillazine.org/Import_bookmarks#From_Internet_Explorer

I know how to do it manually. Manually is not an option in a corporate environment. I need to migrate them automatically with no user intervention when Firefox is installed.

That is not possible. If Firefox is installed then only the Firefox program is installed and it doesn't create a profile. You would need to start Firefox to create a profile and launch the profile migrator to import data from another browser if there is no profiles.ini file present. There may be more browsers installed and it wouldn't have to be IE to import data from.