[Gretl-users] AIC in ADF test lag selection

Dear Gretl users and developers, I noticed that the AIC used in the lag selection procedure of the ADF test is different from the one reported under the regression results. Also, the lag selection would be different if based on the regression's AIC. My questions are: "What formula is used for the selection procedure?", "Why does it differ from the usual one?" Thanks and best wishes, Matteo