rpm --help contains long option entries like:

  -e, --erase=<package>+           erase (uninstall) package
  -F, --freshen=<packagefile>+     upgrade package(s) if already installed
  -U, --upgrade=<packagefile>+     upgrade package(s)

...but the long option syntax does not actually work when invoked like the above, they need to be given like "--erase foo" or "--upgrade foo" instead, i.e. the "=" needs to be replaced by whitespace.  For some options the "=" appears to work (for example --rcfile=foo) but not for any of the above.

No idea if this is an upstream rpm or popt issue, so reporting it here.