Superfluous Updates for a @ManyToOne in OpenJPA 1.2.1

[Christopher Gardner]

Class A has a unidirectional many-to-one relationship with Class B.  I
change a property on a Class A object and persist the object.  The log shows
SQL update statements called for both A and B.  I have no cascade options
set on A's @ManyToOne.  I do not want any updates to B because it's not
logical to do so and it's inefficient. B represents standard, boilerplate
data for many A's.  Also, it adds no value for B to know about A.  No update
is appropriate in this context.  How do I stop updates to B?