libassuan installs shared libs but doesn't have /sbin/ldconfig calls in %post or %postun.
libassuan-2.0.0-4.fc15 has been submitted as an update for Fedora 15. https://admin.fedoraproject.org/updates/libassuan-2.0.0-4.fc15
Package libassuan-2.0.0-4.fc15: * should fix your issue, * was pushed to the Fedora 15 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing libassuan-2.0.0-4.fc15' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/libassuan-2.0.0-4.fc15 then log in and leave karma (feedback).
libassuan-2.0.0-4.fc15 has been pushed to the Fedora 15 stable repository. If problems still persist, please make note of it in this bug report.