There was no overall defined segment limit but there was a limit of ? 4-5 free segments per continent (? 6 in North America) and possibility of purchasing ? 2 extra segments ? per continent meaning an xONE6 had an effective limit of somewhere around 32- 36 segments plus extra purchased segments.

An interesting thread from the early days of Flyertalk with a 35 segment itinerary listed on page 3 -

Those were the days my friend,
I wished they'd never end ,
We'd fly and stay forever and a day,
We'd fly the flights we choose,
So much our butts would bruise,
We were young and sure to fly our way

http://www.flyertalk.com/forum/onewo...orer-fare.html