Incremental data load not able to detect delta if last run is failed

I have encountered an problem incremental data load in PBCS. Let's say there is a failure due to some missing mappings during an incremental data load and assume it's process ID is 101 and DM stores last process ID as '101'. If you correct those mappings and re-run the data load with same source file, it shouldn't able to find any delta and data load completes with warning saying that ZERO records were processed. Does any one encountered this problem? Please help me with working solution other than going for full data load.