In the legacy/character version of our software, we normally prompt for dates using a two digit year (mm-dd-yy), iconving and oconving as needed.  Recently, a user entered "12-31-33" as a date.  The iconv returned -12418 (12-31-1933) rather than the expected value of 24107 (12-31-2033). 

After researching this we discovered that Pick/Rocket and QM both default to dates entered with 2 digit years greater than 30 to be in the 1900's, years less than 30 as assumed to be in the 2000's  Note: iconving a date with a 4 digit year always returns the correct value..  QM does have a config setting that will allow you to override the cutoff, however rather than remembering to change the config setting every few years on every user system, we opted to add code to our legacy system that checks the iconv'ed value and adjusts it as needed.