How to make Drupal 6 search result URL use "-" instead of space?

Example of Drupal 6 search result URL is like this:

http://www.site.com/search/node/Search for something

How to make Drupal 6 search result URL use - instead开发者_运维问答 of space? (below is an example):

http://www.site.com/search/node/Search-for-something

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IMHO, unlike Wordpress, in Drupal, http://www.site.com/search/node/Search-for-something means search for Search-for-something. There is no way except much hackng in core which many people dont want to.