Try rebuilding the curves. Select the curve(s), then select Edit Curves-->Rebuild Curves-->option box. From the Rebuild Curves Option dialog select Unifom, 0to#Spans, then specify the number of spans. I all the curves will have the same number of spans than you can select then all at once an rebulid them all in on step. A note of caution, rebuilding with uniform spans will reshape the curve some.