Your line of thinking is perfectly correct. As it happens, the French circuit breakers always break the neutral. (It's a good thing on TT systems too) Thus, French 3-ph circuit breakers are 4-pole.
From "grounded" and "color" I infer you are American, but it would have been a good idea include that in your profile.
Effectively, you will need to use IEC breakers rather than the conventional American style.
Standard general purpose breakers up to 63A (I think) fall within the IEC 60898 standard. As this is an industrial system, you may need something outside this or something more special. IEC 60947 would then be the appropriate type.
Try googling for IEC 60947 breaker and IEC 947 breaker (The 60- was added to the numbering recently) to find some info for Americans. Breakers are called MCB's in British English, so you should try that to find manufacturers. The trailing numbers with dashes are different standards for breakers, switches, disconnects and a dozen other things that interrupt the flow of electrons in one way or the other.
Have a look at GE Power Controls
Please be aware that whatever you design, it needs to have CE marking. I suspect that you are designing some kind of machinery, in which case the requirements not only apply to the electrical system but also to the machines as such. Things like warning signs, emergency stops and barriers to prevent the machine to cut of the workers hand and so on.
[This message has been edited by C-H (edited 08-15-2003).]