I'm not sure which component is responsible for that behaviour, so please change an assign if necessary.
In 'Update viewer' in a change description window where no description is available a changelog from RPM package (SPEC file) is printed. When there is antispam email address used (which is very common since SPEC file are usually available on the net in as a plan text) an error is displayed (instead of a changelog):
The developer logs will be shown as no description is available for this update:
Could not parse header: 'Foo Bar <foo.foo[AT]bar.com>', expected: 'Firstname Lastname <email@example.com> - version-release'
In my opinion regexp could be simplified to detect email part as <*>, not necessary with '@' and at least one '.'.
We moved the upstream bugtracker to GitHub a long time ago. If this issue still affects you please re-create the issue here: https://github.com/hughsie/PackageKit/issues
Sorry for the impersonal message, and fingers crossed your issue no longer happens. Thanks.