Hey AussieRock.
I had the same thing happen to me.
I was trying to find the example for you of where it happened, but I haven't been able to dig it up.
Basically, when you export, the system is having a problem with wanting to be a fixed size. If you can change your source from ntext to text you won't have this problem, or alternatively, write code to convert the field to a fixed width prior to doing your output.
This fixed it for me anyway... sorry that's a bit vague but if I find the example I'll post it for you.