/ is always a command char, but your if statement will only check if the text doesn't start with the second command char, so, for example, it would send commands if they were prefixed with / but ~ was your second command char.
This fixes that:
Code:
on *:input:*:{
if (!$istok(/ $readini($mircini,text,commandchar),$left($1,1),32)) {
msg $active $+($chr(3),$base($rand(0,15),10,10,2),$1-)
halt
}
}
