Howard - Thanks for the reply. Each task in a LiveCycle process could be run by a different user however every call to the LiveCycle server must be authenticated..hence you have to log in to workspace before performing an action..or when making API calls via webservices or the java api you must supply a credential.
If you look at the way the FileNet and Documentum connectors are built Adobe has used a custom authenticator to actually store the credentials of the user who is logged into the service in a credential cache. Then on their components they allow you to check "run as process context" or something to that effect which will basically look in that cahce to find the username and password.
Before I went down this route (as I know it will work) I was trying to find out if Adobe had any other place that they store the credentials that came into the service call (after all a task in an orchestration is simply a service call). That way I could retrieve it and build the connection to my backend system with that userid/password.