[maxmsp] Bad curve~ arguments

I'm running into some sort of type casting error with the curve~ object. I'm building a message like "100, 200 50 0.5" through a series of calculations and prepends / appends, but when I finally pass it over to curve~ it spits back an error. If I print the same message and paste the result into a message box and use that on curve~, it works. I'm guessing the message is being treated as one big symbol instead of a list of arguments? Any quick fix?

Thanks!