See the JIRA description for details. I've lower-cased the case values so that they will match against the lower-cased filter operation. I've also specified that if the filterValue is a date field ('date.struct' as a value), it will attempt to parse it. Previously, the check was only for 'struct', and I've left this in in case there was some behaviour being relied upon that used that value (though given that the case statements were not evaluating this would be surprising).
When filterLink tag was pointing to a different controller than the current, the sort params became invalid. This has been fixed. This change also makes it possible to explicitly set the sort and order parameters as attributes to the filterLink tag.
…nd lower casing the i18 class name for matching with grails docs scaffolding http://grails.org/doc/latest/guide/i18n.html#scaffoldingAndI18n