Hello @ALL; Today I wanted to use istringstrems in my prog. I am using g++-4.0 from debian testing. After including only sstream, iostream string the folowing error ocured: /usr/lib/gcc/i486-linux-gnu/4.0.3/../../../../include/c++/4.0.3/bits/sstream.tcc : In member function 'virtual typename std::basic_stringbuf<_CharT, _Traits, _Al loc>::int_type std::basic_stringbuf<_CharT, _Traits, _Alloc>::overflow(typename _Traits::int_type)': /usr/lib/gcc/i486-linux-gnu/4.0.3/../../../../include/c++/4.0.3/bits/sstream.tcc :112: error: expected unqualified-id before '(' token /usr/lib/gcc/i486-linux-gnu/4.0.3/../../../../include/c++/4.0.3/bits/sstream.tcc :114: error: expected unqualified-id before '(' token I want to repeat the Problem: I didn't use any istringstream. I included only the needed headers. If I do these including in a small test programm it works. The error does not happen with g++3.3. Can you please help to get this work with g++4 compiler options I used are: g++ -O0 -g -pipe ..... best regards