Webalizer: Redo current month's stats?

[Tormente]

While trying to get webalizer to process some previous days missing stats (due to a segfault problem), I ended up no only with missing stats for those days, but now the current month's report spiked with false data.

How can I have Webalizer redo the current month's stats without losing any previous stats?

And for my bonus question: how can I get those missing days back without screwing everything up?

Thanks for any info.