IO extended card inputs/outputs can not be read/written by IMC card

With SoMachine v4.x ATV61/71 IO extended card inputs/outputs can only be accessed by IMC card if all of them are at least accessed once in application code.
In other words, following code has to be added :

VAR
    tmp_ai3, tmp_ai4 : WORD;
    tmp_ao2, tmp_ao3 : WORD;
    tmp_li11, tmp_li12, tmp_li13, tmp_li14  : BOOL;
    tmp_relay4, tmp_lo3, tmp_lo4 : BOOL;
END_VAR
--------------------------------------------------------

tmp_ai3 := DRIVE_AI3;
tmp_ai4 := DRIVE_AI4;

DRIVE_AO2 := tmp_ao2;
DRIVE_AO3 := tmp_ao3;

tmp_li11 := DRIVE_LI11;
tmp_li12 := DRIVE_LI12;
tmp_li13 := DRIVE_LI13;
tmp_li14 := DRIVE_LI14;

DRIVE_RELAY4 := tmp_relay4;
DRIVE_LO3 := tmp_lo3;
DRIVE_LO4 := tmp_lo4;