setPolicy requires checkout?

[Mat Lowery]

According to the JCR 2.0 API documentation of 
AccessControlManager#setPolicy(String, AccessControlPolicy):

"A VersionException will be thrown either immediately, on dispatch or on 
persists, if the node at absPath is read-only due to a checked-in node. 
Implementations may differ on when this validation is performed."

Doesn't this assume too much about the implementation?  Using Jackrabbit 
2.0.4 defaults, rep:policy's onParentVersion is IGNORE so it technically 
doesn't require a checkout but the implementation actually does make 
sure it is checked out in ProtectedItemModifier.

I'd like to make an ACL modification without creating a new version.  
Any ideas?
<http://www.day.com/maven/jsr170/javadocs/jcr-2.0/javax/jcr/RepositoryException.html>