Please can anyone help?

I have an If formula set up to extract info from one worksheet to another
when a certain value is entered. basically the data is in columns of our
code, their code and description. the formula for the numeric columns is fine
and returns the correct data however the formula to return the description
text only returns a 0. can anyone see what i have wrong in the formula?

=SUMIF('Oct 07-Sept 08'!A5:A108,Sheet1!A8:A37,'Oct 07-Sept 08'!B5:B108)

Kind regards

Jamie