FYI, here's the response to the gcc invocation:
knoppix@1[~]$ gcc -v test.cpp -o test
Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v --enable-languages=c,c++,java,f95,objc,ada,treelang --prefix=/usr --enable-shared --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --enable-nls --program-suffix=-4.0 --enable-__cxa_atexit --enable-clocale=gnu --enable-libstdcxx-debug --enable-java-awt=gtk-default --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-4.0-1.4.2.0/jre --enable-mpfr --disable-werror --with-tune=i686 --enable-checking=release i486-linux-gnu
Thread model: posix
gcc version 4.0.4 20060507 (prerelease) (Debian 4.0.3-3)
/UNIONFS/usr/bin/../lib/gcc/i486-linux-gnu/4.0.4/cc1plus -quiet -v -iprefix /UNIONFS/usr/bin/../lib/gcc/i486-linux-gnu/4.0.4/ -D_GNU_SOURCE test.cpp -quiet -dumpbase test.cpp -mtune=i686 -auxbase test -version -o /tmp/cclr3aiv.s
ignoring duplicate directory "/usr/lib/gcc/i486-linux-gnu/4.0.4/../../../../include/c++/4.0.4"
ignoring duplicate directory "/usr/lib/gcc/i486-linux-gnu/4.0.4/../../../../include/c++/4.0.4/i486-linux-gnu"
ignoring duplicate directory "/usr/lib/gcc/i486-linux-gnu/4.0.4/../../../../include/c++/4.0.4/backward"
ignoring nonexistent directory "/usr/local/include/i486-linux-gnu"
ignoring duplicate directory "/usr/lib/gcc/i486-linux-gnu/4.0.4/include"
ignoring nonexistent directory "/usr/include/i486-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
/UNIONFS/usr/bin/../lib/gcc/i486-linux-gnu/4.0.4/../../../../include/c++/4.0.4
/UNIONFS/usr/bin/../lib/gcc/i486-linux-gnu/4.0.4/../../../../include/c++/4.0.4/i486-linux-gnu
/UNIONFS/usr/bin/../lib/gcc/i486-linux-gnu/4.0.4/../../../../include/c++/4.0.4/backward
/UNIONFS/usr/bin/../lib/gcc/i486-linux-gnu/4.0.4/include
/usr/local/include
/usr/include
End of search list.
GNU C++ version 4.0.4 20060507 (prerelease) (Debian 4.0.3-3) (i486-linux-gnu)
compiled by GNU C version 4.0.4 20060507 (prerelease) (Debian 4.0.3-3).
GGC heuristics: --param ggc-min-expand=99 --param ggc-min-heapsize=129331
test.cpp: In function 'int main()':
test.cpp:8: error: 'cout' was not declared in this scope
test.cpp:8: error: 'endl' was not declared in this scope

As I read this, gcc is looking in a bunch of wrong directories for the C++ include files.

--Fred