Can Matrix Variables ever be used without a corresponding @PathVariable? Or, must they always be bound to a @PathVariable either explicitly using the pathVar attribute or implicitly to the last @PathVariable on the URI?

For example, I try to use the following
Code:
@RequestMapping(value = "/EventThroughputStats", method = RequestMethod.GET)
@ResponseStatus(HttpStatus.OK)
public EventThroughputStats eventThroughputStats(
        @MatrixVariable final Date startTime,
        @MatrixVariable(required = false) final Date endTime,
        @MatrixVariable(required = false) final String[] hosts
        ) throws IOException {
}
But receive an HTTP 404 error message with /EventThroughputStats;startTime=2013-01-27.

The same appears to be the case when I bind the @MatrixVariable to a Map<String,String>.

Thanks for your help.