Clarification on SAML2 "Time Values"

In section 1.3.3, "saml-core-2.0-os" specifies:

All SAML time values have the type xs:dateTime, which is built in to the W3C XML Schema Datatypes
specification [Schema2], and MUST be expressed in UTC form, with no time zone component.


Now [Schema2] (which is "http://www.w3.org/TR/xmlschema-2") does not
define the term "UTC form". Furthermore, according to [Schema2],
the "Z" suffix is part of the timezone specification.
Thus, an SAML time value with a "Z" suffix can be seen as
one having a "time zone component". However, the example
in section 5.4.6 of "saml-core-2.0-os" uses such a "Z" suffix.


Should section 1.3.3 be interpreted as
"MUST be expressed in the canonical "dateTime" representation
(section 3.2.7.2 of [Schema2]) for timezoned values
(i.e. expressed in UTC with "Z" as time zone component)."
or is the "Z" suffix in the example wrong?

--
Dieter