Unicode categories in regexps?

Is there anything for ruby that will give me access to unicode character
categories in a regexp like function?

For instance, say I want to replace all punctuation with a space, in a
unicode-friendly way that will work with any langauges script in
unicode. Unicode does provide character classes to make this possible,
and other languages built in regexp features support that… but do I
have any options in ruby?

Thanks,
Jonathan