Re: Old for scope rules (/forScope-) don't work with STL declarations?

In trying to get hundreds of legacy C++ projects compiling under VS
2005 from 2003, I turned off the proper for-loop scoping rules using
/forScope-

It works fine with for loops declaring ints, but I got an undeclared
identifier error when referencing a for-declared STL iterator. I tried
std::string too, out of curiosity, and it doesn't behave properly
either.
Here's a meaningless example meant to demonstrate the problem only:

...
for( int xx=0; xx<10; ++xx)
{
}
result = (xx==10); // WORKS FINE
for( std::string yy; !yy.empty(); yy.clear())
{
}
yy.clear(); //IN VS2005: error C2065: 'yy' : undeclared identifier'
...

Any idea what might be going on here? Why would STL classes be any
different than built-in types? (I tried declaring my own struct in the
for loop, and it worked as int did.)