[TYPO3] Cannot give backend groups access to Questionaire (pbsurvey)?

[Bing Du]

Hi,

Typo3 V4.0.4
Questionaire (pbsurvey) 1.0.8

In the configuration of a backend group (this group has everybody and
defines basic access permissions.), I selected

Questionaire item
Questionaire Result
Questionaire Answer

in both 'Tables (listing)' and 'Tables (modify)' box, but after save and
close, I went back to check this group setting, the above Questionaire
changed back to unselected.  I've tried several times to no avail. Anybody
ever seen such a problem and know why?

Thanks in advance,

Bing