integer 32-bit to datetime data type conversion

Hi, I need to retrieve "day of week" values from 32-bit integer values (e.g. 951231) in a informix database. I know the conversion function is weekday(date/datetime). But, I don't know what is the best way to convert a 32-bit integer to a date/datetime data type. Any suggestion is appreciated. If possible, please E-mail me because I don't read this group regularly. Thanks in advance. - Eric