DeltaV methods on locked non-VCR: which response code?

Hi,

assume
1) a non-collection *non-VCR* resource at /foo.xml which is *locked*
2) an ordinary collection resource at /bar which is *locked*.

We are wondering what the response status code should be in these particular
cases (403, 409, 423, ???):

CHECKOUT /foo.xml
CHECKIN /foo.xml
LABEL /foo.xml
REPORT /foo.xml
UPDATE /foo.xml
VERSION-CONTROL /foo.xml

MKWORKSPACE /bar

Regards,
Peter