safe_key "0" problem

When I validate a required select list option that has a safe_key "0", it is always considered empty.

Please also read this webform issue #10 by quicksketch: #883626: 1st choice (keys with "0") of select options (as checkboxes) do not save nor email

I also use the webform validation module to verify if one of the checkboxes is selected. When I select the first option (zero as key value) the module prompts me that I have to select a value.
This is probably a separate bug in Webform Validation. Since the checkboxes are submitting a value of "0", it's easy to accidentally not capture the value since in PHP "0" == FALSE == NULL.