dlsym problem

hi

i'm trying to enable my software to use plugins. i've read a lot about the dynamic loadable libs...
the following problem occurs:
when i compile my small example plugin:

#include <stdio.h>
int
run( )
{
        printf( "hallo!!!!!!!!!!!!!\n\n" );
        return 0;
}

by
gcc -fPIC -DPIC -c main.c
gcc -shared -lstdc++ -o main.so main.o

and also compile my plugin-loader:
#include <dlfcn.h>
#include <stdio.h>
#include <iostream.h>

typedef int entrypoint( );

int
main()
{
        char *errormsg;
        void *module = NULL;
        entrypoint *run = NULL;

        module = dlopen( "/tmp/tmp/main.so", RTLD_NOW );
        //module = dlopen( "/usr/local/lib/libqtgui.so", RTLD_NOW );
//      module = dlopen( "/tmp/tmp/libsuper.so", RTLD_NOW );
        if( !module )
        {
                printf( "superscheisse" );
        }

        run = (entrypoint*) dlsym( module, "run" );
        if( errormsg = dlerror( ) )
        {
                printf( "nei: %s", errormsg );
        } else {
                printf( "aha!\n\n" );
        }
}

by
g++ super.c  -o super -ldl
everyting works fine...

but when i compile the plugin (the first one) - i got an error while dlsym:
./super: undefined symbol: run

there seams to be a problem with the c++ compiler?!

i'm using Mandrake 8.1, g++ version: 2.96

any hints?

thanks, raphael