System update

[Doug Hardie]

I installed 7.0 release when it first came out.  However, because of  
the TCP problems with users on cable modems I had to switch to Stable  
to get the fix.  I haven't updated the source since then and now there  
are some updates on the verge of being released that need to be  
included.  However, I can't tell if the fixes for the networking issue  
have been included in the security releases or not.  Since these are  
production servers I don't want to just grab some random version of  
stable unless thats the only way to get all the required fixes.  How  
do I find out which version I should upgrade to?  If I can go back to  
a security release I suspect I will need to delete all of /usr/src, / 
usr/obj, and then reinstall the original source from the 7.0 release  
cd and then upgrade vi csup.