by that thinking Khaled can be arrested for building mIRC, which allows DCC, which allows these files to be shared. He didn't need to add the capability to mIRC.
Or perhaps stanley should be sued for making knives, utilised in crimes everywhere.
Maybe ICI should be sued for making dynamite.
Just making somethign available shouldn't make you an accessory, you didn't make people use it in an illegal manner. People can think for themselves and if they choose to do illegal things then that's their decision. I don't think the people who make the tools are responsible.