Fedora 11 has version 0.14 of perl-Net-OAuth. This version only supports OAuth 1.0, which is vulnerable to a session fixation attack (details at the URL above). Upstream Net::OAuth implemented OAuth 1.0A in 0.16; the latest Net::OAuth is 0.19.
perl-Net-OAuth-0.19-1.fc10 has been submitted as an update for Fedora 10. http://admin.fedoraproject.org/updates/perl-Net-OAuth-0.19-1.fc10
perl-Net-OAuth-0.19-1.el5 has been submitted as an update for Fedora EPEL 5. http://admin.fedoraproject.org/updates/perl-Net-OAuth-0.19-1.el5
perl-Net-OAuth-0.19-1.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/perl-Net-OAuth-0.19-1.fc12
Weird, looks like the Fedora updates system didn't post the fc11 package link here... At any rate, I've tested both the fc11 and fc12 packages from koji on my Fedora 11 box, and they both work well.
perl-Net-OAuth-0.19-1.fc10 has been pushed to the Fedora 10 stable repository. If problems still persist, please make note of it in this bug report.
perl-Net-OAuth-0.19-1.fc11 has been pushed to the Fedora 11 stable repository. If problems still persist, please make note of it in this bug report.
perl-Net-OAuth-0.19-1.el5 has been pushed to the Fedora EPEL 5 stable repository. If problems still persist, please make note of it in this bug report.