portupgrade index generation error

[dave]

    Hello,
I'm running a 5.2.1 system with portupgrade on it. I'm trying to update my
ports and am getting an index generation error when i run:
portsdb -Uu
I've deleted the entire ports tree, and rerun cvsup, refetched the entire
tree, reran portsdb -Uu and am still getting the same index generation
error, this is not occurring on the same package, which leads me to believe
i've got a corrupted database somewhere, no idea where.
    Any help appreciated.
Thanks.
Dave.