Question on sharing SMF login information

[MechSpecs]

My question is really rather simple (see the sarcasm?)

Is there a way to share login information from SMF to another site? My partner and I are looking to have a single user login shared between the SMF portion of our site and another custom job that my partner is working on that will be hosted on a sub-domain of our main site (although the sub domain points to a different physical server). Is there something out there that shows how this can be done? I did some searches and I found bridges for SMF and Wordpress and things like that but nothing that supported custom sites.

[margarett]

If they were on the same server, you could perform it with SSI.
http://wiki.simplemachines.org/smf/Category:Integrating_SMF

In your case, you would need something like the REST API:
http://www.simplemachines.org/community/index.php?topic=458832.0