Hmmm if he's using the HSF that came with the 6000+ it should be ok. Though it sounds more like he doesn't have any airflow in the case. If 46c is the ambient system temp, then god knows how high the cpu temp is going under load. What kind of fan layout does your case have for airflow? Or what make/Model of case is it?
I don't know if the 6000+ and the Phenom processors come with the same hsf unit or not. The one that came with my 9600BE was the one with all thin aluminum fins, copper base, and copper heatpipes. The thermal paste on that appeared to have the same look and consistency as what comes with the Zerotherm Nirvana HSF unit, which as far as I can tell is just a small tube of ZeroTherm ZT100 thermal grease. That wouldn't suprise me because Apack/Zerotherm is also an OEM HSF supplier company. With that unit you should likely be seeing idle temp around 30-32c, and load temp around 40-45c at least thats my experience with it. But that is if it's installed properly.
If it was like the HSF unit that came with the 65w Windsor X2 4200+ I had, then that would be an all aluminum heatsink with thick fins. Fine for a 65w proc that rarely draws over 51w under full load, but not for an x2 6000+ that probably runs closer to 110w full load.
If it's possible, I'd put a couple more fans in the case for airflow, and if you really want to, get a better cpu cooler. Zalman 9700, ZeroTherm Nirvana 120, and BTF 90, Thermalright Ultra 120 is good as well, and grab some arctic silver 5 or Arctic Cooler MX-2 thermal compound.
And another question I dont think has been asked. When you upgraded to the 6000+ did you clear your cmos bios settings and redo them afterwards? That can also be an issue if your bios is still trying to use the settings from the older processor.