Spring C&I spec: interface of a service when no <sca:service> elementis present

Line 457 [1] says: "interface.java child element is present with the 
@interface attribute set to the fully qualified name of the interface 
class introspected from the bean class declared in the @class attribute 
of the <bean/> element."

What happens if the class implements multiple interfaces?
Why is introspection necessary, wouldn't it be easier to just set it to 
the value of the @class attribute.

Wanted to see if others see this as an issue as well before I file one.

Thanks.

-Anish
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[1] 
http://www.oasis-open.org/apps/org/workgroup/sca-j/download.php/39024/sca-springci-1.1-spec-WD05.pdf