sequence inside a choice

[Ryan]

Is it legal to have something like:
<xs:complexType name="transaction">
<xs:choice minOccurs="1" maxOccurs="unbounded">
<xs:sequence minOccurs="1" maxOccurs="unbounded">
<xs:element name="account_login"
type="login_data" minOccurs="0" maxOccurs="unbounded" />
<xs:element name="create_id"
type="tbl_iv" minOccurs="0" maxOccurs="unbounded" />
<xs:element name="org_create"
type="org" minOccurs="0" maxOccurs="unbounded" />
</xs:sequence>
</xs:choice>
</xs:complexType>

Notice how there is a sequence inside a choice and nothing else.

Also, what do the minOccurs/maxOccurs modifiers do on the choice and
sequence grouping?