extending a classes from another package?

[elh.maayan]

hi..

i'm buidling a small framwork that wraps around xml Element objects
(in xom) i have these packages:
com.product.xml
AbstractElement
AbstractValueContainer
VallueException
com.product.xmlValues
StringValue
ListValues
NumericValues

each of the values extends AbstractElement

now some of these values classes should recieve other Value Classes
in their setters, but internally extract their internal XmlElement and
append it their own. my problem ,is that on one hand i wanna expose
the getInternalElement method only the value classes, but on the other
hand i don't want to make it public. so it's either protected or
package level,