silly: sed and simple regex that doesn't work

[Aleksander Piotrowski <aleksander_(_dot_)_piotrowski_(_at_)_nic_(_dot_)_com_(_dot_)_pl>]

Hello

I've got following code which doesn't work:

	echo "foo123bar" | sed -e 's/\([0-9]\+\)//'

Of course, as I'm a lamer this is obvious that above code doesn't work
(outputs "foo123bar") but... 

... it works fine (outputs "foobar") with GNU sed. I don't get it. Is there
anything special in above regex that makes it GNU sed-only?

Thanks for patience,

Alek

ps. This is -current system.
-- 
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