Xnews out of memory problem

Thanks to giganews' outstanding completeness and retention, I'm faced with
a new woe: due to the large amount of headers that I need to download
(which sometimes number over 10 million), it becomes fairly often to run
into the dreaded "out of memory" problem. Make no mistake, my system is
decidedely high-end, with AMD dual core 2.6ghz and 2 GB OCZ dual-channel
ram, and the total amount of virtual memory is set to the max 4GB.

Correct me if I'm wrong, but it seems to me that Xnews makes no effort to
conserve the usage of physical ram, it simply downloads all headers into
ram, before sorting and then storing the headers. If there are too many
headers to fit in the physical ram, kaboom, because it doesn't even try to
make room by writing freshly-downloaded data to the hard drive. I've tried
to download headers in a piece-meal fashion, sadly to avail, because Xnews
insists on loading old headers into physical ram before downloading the new

I've become really fond of Xnews, and hope there is a solution to this
problem: ie. a setting in the setup (where I've failed to find anything
relevant so far), or even a magic statement in the ini file.

Your help would be most appreciated.