'default_random_engine' is not a member of std

I have found many questions to this topic but all problems seem to be related to not compiling with c++ 11. My code is

#include <random>
int main(int argc, char *argv[]){
    std::default_random_engine generator;
    return 0;   
}

even though I compile with

gcc -std=c++0x testmain.cpp

giving the error that default_random_engine is not a member of std. The progam is compiled on a remote machine, which I do not maintain myself but

gcc -v

yields a version of 4.4.7.

Any ideas?