That depends on how it's set up. If the password encryption methods are
compatible (I don't if they are), it would be easy for dimacs to set up
a nightly script that transfers the info from the operating system to
the web server.
In the longer term, several companies are developing "directory
services" based on common standards that promise to provide a "single
login" for all the services you use. (Sample propaganda at
http://home.netscape.com/comprod/columns/techvision/ldap.html ).
PB