It's not so hard to make a meego sd, and loading the kernel (not flashing it - next reboot gets you back to maemo) is just one command. I would prefer it over wiping, except if I had a recent backup. Search how to install meego de on n900 sd.

Also maybe m4r0v3r is right and wiping does not help. I know for sure it doesn't reset the lock code. But will it enable you to reach the terminal? I don't know.
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