I'm trying to do a calculation with multiple Ifs.

On Sheet2, I have the following:

Employee Date Started Date End Hours Available
John Doe 4/1/2007 6/1/2007 30
Joe Smith 4/22/2007 10/1/2007 25
John Doe 6/2/2007 10/1/2007 15

On Sheet1, I have the employees' names, Week Ending Date (which is a Sunday)
and a column where I need the calculation. So it looks like this:

Employee Week Ending Hours Available
John Doe 4/8/2007
John Doe 4/15/2007
John Doe 4/22/2007
Joe Smith 4/8/2007
Joe Smith 4/15/2007
Joe Smith 4/22/2007

I am trying to put the Hours Available between the Date Started and Date End
on Sheet1.

So in this instance, John Doe would have 30 hours for 4/8, 4/15 and 4/22;
Joe Smith would have 25 hours for 4/22/07.

Is there a way to do this? Help!