Removing non business days & hours

How do I calculate the number of days, hours & minutes between 2 value's and exclude non business days and hours...? For example, I have 2 time/dates stamps; 1. the time/date an incident was logged (say 01/21/09 09:30). 2. the time/date the incident was resolved (say 01/29/09 19:30). In real time thats 7 days & 10 hours. But in business terms its 6 days 2.5 hours (working Monday - Friday, 9 - 5 (8 hr days)).

I can use 'networkdays' function to calculate working days but it ignores the time completely.

I'm using Excel 2007

HELP!!!??


Cheers, Jason