Summing values from range with if statement

[truohol]

Hey all!

I am new to this forum, because I have been able to solve my problem by my self so far, but now I have met an impossible problem.

The problem is following:

I have 31 dates on cells from D7 to D37, lets say for example 1.1-31.1.
On sheets from E7 to E37 I have amount of hours, i have worked on a current day.

What I would like to have is a function, which sums all the hours together that have been done on Monday from the range E7:37. I have tried following on a cell: =sumif(D7:D37;WEEKDAY(2);E7:E37).
I know how I could do it with a fill function and then sum those together, but in that case I would have 32 different cells needed to do the trick.

Could anyone help me, I am desperate because excel has won me

Cheers,

Tuomas/Finland