Use timezone provided in input dates in extended function "checkDate"
Extended function checkdate checks if current (local) date is within a start and/or end (GMT) dates range. It is used to allow access only during a certain period of time.
Right now it's not possible to adjust the time used for this check, while the similar extended function checkLogonHours has this option through the time_correction parameter.
As of @maxbes suggestion below, instead of adding a time_correction new parameter, the function should be adapted to interpret the timezone provided in input dates, eg:
Date in New York timezone:
199412160532-0500
No timezone or "Z" value in input date will still default to GMT.
Note: Change needs to be compatible with safe jail.