SSIA. There was a symlink in /usr/lib/mozilla-1.7.13/plugins but Seamonkey uses /usr/lib/mozilla-seamonkey-1.0.3/plugins. Even if you reinstall the plugin package, the symlink isn't placed to the new plugins directory because the install scriptlet looks for the plugins directory in such a way that it fails with seamonkey.
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2006-0744.html