Incorrect RegEx for XsdTimezoneComponent

[C-Bookie]

Reading section 3.2.7.3 of XMLSCHEMA-2, I belive that XsdTimezoneComponent should match '+00:00' & '-00:00', Reading as
((\+|-)(0[0-9]|1[0-9]|2[0-4]):(0[0-9]|[1-5][0-9])|Z)?
instead of
((\+|-)(0[1-9]|1[0-9]|2[0-4]):(0[0-9]|[1-5][0-9])|Z)?