Limited Transaction Logging

Is it possible to implement limited transaction logging in Informix? We have a very large system (in terms of number of programs) that does not use any transaction logging whatsoever. As a short term fix to address our highest areas of risk, we would like to immediately implement transaction logging for certain critical activity, and then go back and do the rest of the system. Unfortunately, we are currently "between" DBAs (not that our former DBA was able to answer that question), and don't have anybody here who can tell us whether this is possible. For example, most programs in the application do quite a bit of intermediate inserting, updating, and deleting to temporary tables that we would not want to log, but we would like to log activity to the permanent tables. Similarly, there are a large number of programs in the system, and it would take quite a while to implement transaction logging across all of the programs. Therefore, if we could prioritize by adding it on the most critical programs first (e.g., the inserts/updates to certain key tables), we could reduce our risk in the most critical areas in the shortest amount of elapsed time. Can this be done? Can we implement transaction logging within selected programs only, and can we implement transaction logging for selected inserts/updates/deletes within those programs? For reference purposes, the application is running on On-Line 5.02, is written in Informix 4GL, and runs in a Unix environment. Any help would be greatly appreciated.