There is no bug in the rules. Czech Checkers is just a variant played in our country and the rules details had been consulted with top Czech Checkers players.
From Checkers rules:
"If the player has more possibilities to capture opponent's pieces, he/she can select any of them. However, when a king or queen (in variants) can make a jump, the player cannot select a pawn to jump with."
(do skréše) Vlitni do špilo v to rano! Při vepoštěni taho si aj se sópeřem namontojte "táhnót a pobét toť" a furt dokola oževojte léstek bóchánim do klávese F5! (TeamBundy) (okázat šecke vechetávke)