The above posts need to mention the country in question, otherwise they are meaningless!
In the UK, and all of Europe
AFAIK, the holder of a JAA (now EASA) PPL can fly VFR above a solid overcast, as of April 2012.
Before that date, UK JAA PPL holders had to be in sight of the surface (exactly what that meant was never defined in the law).
The ability to fly VFR above a solid overcast is a basic ICAO position, worldwide.
How you climb up and down while maintaining VFR is another matter.