Problem description: 
When using the SUMIF function through the function wizard, a Criterion with text value is being marked with a single quotation mark, which results in a 0 value of the sum.
When the single quotation mark is manually being changed to a double quotation mark in the formula, the function works correctly.

Example: =SUMIF(E2:E8;'Paid';C2:C8) is the formula gained through use of the wizard. This will result in an incvorrect sum
When being corrected to =SUMIF(E2:E8;"Paid";C2:C8), the result is correct.

Steps to reproduce:
1. Add the following data to a spreadsheet:
A1 = 1; A2 = 2, A3 = 3, A4 = 4, A5 = 5
B1 = Paid; B2 = Unpaid; B3 = Paid; B4 = Unpaid; B5 = Paid

2. Enter a SUMIF formula through the function wizard in C1 with the following arguments:
Range = B1:B5
Criteria = Unpaid
Sum range = A1:A5

Current behavior: Formula =SUMIF(B1:B5;'Unpaid';A1:A5) is generated, the result gained in C1 is 0

Expected behavior: The result in C1 should be 6

This can be obtained by manually changing 'Unpaid' to "Unpaid" in the formula.

Platform (if different from the browser): Ubuntu 12.04 LTS
              
Browser: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:12.0) Gecko/20100101 Firefox/12.0