This is content of my ~/.config/kcmkmailsummaryrc
Code:
[CheckState]
Current=x-1
Selection=c13,c12,c8,c4,c7,c3,c18,c15,c6,c17,c9,c5,c11,c16,c14,c32,c33,c34,c35,c36,c37,c38,c39,c40,c41,c19,c20,c21,c22,c23,c24,c25,c26,c27,c28,c29,c30,c68,c31
...