I've written and released some Perl modules to help manage Intermapper assets through the HTTP API. The modules provide access to the user, device, interface, map and vertex information (query only) and does support CRUD actions on devices and users. It does not cover all available assets (like retention policies and schemas) and does not provide advanced queries (filtering on specific values for instances) but the initial functionality is present. Updates will be coming over the next few weeks.
http://search.cpan.org/~beatnik/Net-Intermapper/