Why is config admin checking for empty collections in Configuration values?

[David Jencks]

While writing a test I discovered that config admin doesn't like empty 
collections or collections with empty values as configuration values.  After 
searching the 5.0 config admin spec for a while I can't find any support for 
these restrictions, and they are not applied to arrays.  What is the 
justification for these checks?

Here's the code I'm asking about (CaseInsensitiveDictionary lines 309ff)

            if ( collection.isEmpty() )
            {
                throw new IllegalArgumentException( "Collection must not be 
empty" );
            }

            // ensure all elements have the same type and to internal list
            Collection internalValue = new ArrayList( collection.size() );
            type = null;
            for ( Iterator ci = collection.iterator(); ci.hasNext(); )
            {
                Object el = ci.next();
                if ( el == null )
                {
                    throw new IllegalArgumentException( "Collection must not 
contain null elements" );
                }


thanks
david jencks