External links in new windows without using 'target'

The default Drupal 5.0 theme (and previous default Drupal themes) uses XHTML Strict. There are reasons this is probably a bad idea but, in the spirit of eating my own dogfood, I'm going with it for now.

One gotcha I discovered right away is that the <a> tag does not allow the "target" attribute in XHTML Strict (nor does it in HTML Strict). However, the behavior of <a target="_blank"'> can be replicated in XHTML Strict with semantic markup and scripting.