I had a similar problem after upgrading perl on my rh9 box. My solution was:

mv /usr/bin/perl /usr/bin/perl-5.8.0
cp /usr/local/bin/perl /usr/bin/perl-5.8.6
ln -s /usr/bin/perl-5.8.6 /usr/bin/perl
[download]

...restart apache. Note, however that there is probably a right way to do it and my money says that this solution is not it - but it might at least provide you with a temporary solution.