ctime and asctime handle this differently:
-asctime allows years from 1900, since it offsets the years. Values given supplied that (negative) let the function output garbage. Ref: http://www.cplusplus.com/reference/clibrary/ctime/tm/
-ctime gets the number of seconds passed and converts these to a struct which is passed to asctime in this implementation. The first second is defined to be on 1st jan 1970. Ref: http://www.cplusplus.com/reference/clibrary/ctime/time_t/

Anyway I'll most likely test tkreuzer's crt time implementation from the 64bit branch. If if works out good it'll replace the current crt time code soon.

Best regards
G. Schneider