OK, probably missing headers as Daniel said. Try:

    apt-cache search stdc++ | grep dev

On my 10.04 box I have libstdc++6-4.4-dev, but it may be different for 
you.

Note that Ubuntu 7.10 went end-of-life in April 2009, so you really need 
to upgrade that box. You won't be getting any critical security updates.

https://wiki.ubuntu.com/Releases

A single upgrade to 8.04 will get you support until April next year, and 
from there you can upgrade directly to 10.04.

Regards,

Brian.
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