Well, some comments about this: 1 - I don't know if it's very normal that a query return "version" nodes. If the spec. does not says something about this, then maybe we're looking at a possible improvement area.
Ok, and now. My frozen node has {http://www.jcp.org/jcr/nt/1.0}frozenNode as primaryTypeName attribute value (I'm putting this because maybe it could affect the xpath queries). So: 2 - //element(*,mix:content)[jcr:contains(.'phrase')] : This query returns two results. One of type mix:content and another one of type nt:frozenNode 3 - //element(*,mix:content)[jcr:contains(.'phrase') and @jcr:primaryType !='nt:frozenNode'] : This query returns 0 results. 4 - //element(*,mix:content)[jcr:contains(.'phrase') and @jcr:primaryType =='nt:frozenNode'] : And also very interesting; this query does not return anything. It hangs !!! Comments? Thanks!