RPC Services with getHistory/getActivity

Hi, I am creating an application that currently utilizes the RPC features of JIRA. However, I have found out that there is no support for retrieving History or Activity information. I am currently using XMLRPC, but SOAP does not have the functionality either (as far as I can tell). There is a getComment() function, but no getHistory or getActivity?

My use case:

I am creating a script that will constantly search the JIRA database for new changes. IE, if issue PROJ-4 was recently changed from open to closed, or someone posted a new comment on PROJ-4, I would like to know about it. I have this scripting working for Bugzilla and Trac, where I would iterate through the history to see if these changes occurred. With JIRA, I see no easy way of doing this. It would be nice if these RPC functions could be implemented. Thank you.