Thank you so far. Unfortunately tagmp3 will only change ID3v1 tags which makes it pretty useless if a mp3 has already v2 tags. Same for id3tool mentioned first on the macosxhints page.
Further down there people talk about an
id3v2 frontend for
id3lib, which appears to do exactly what I want, but I get linker errors like:
ld: Undefined symbols:
__
std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >::_Rep::_M_dispose(std::allocator<wchar_t> const&

std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> >::basic_string[in-charge](std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&

...
It appears that g++ does not find libstdc++ and I have no clue why.
So if anyone has a solution for this problem or can tell of any other ID3v2 commandline editors I'd appreciate it.
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