Disabling a textarea's #resizable causes body field to disappear

This is mostly reposting a problem I had raised on the forums at http://drupal.org/node/799292, but, to set it up here for possible action (and in the hopes that I'm posting it in the right place):

I've been converting a D5 site to run on D6, and in the previous version of the site, I had wanted, for some reason or another, to disable the resizable aspect of textfields. For better or worse, I did this by adding the following code to my theme's template.php file:

function phptemplate_textarea($element) {
     $element['#resizable'] = false ;
     return theme_textarea($element) ;
}

I'm not sure where this came from; I might have come up with it myself when I was young(er) and foolish(er). In any case, it worked fine in D5. However, in D6, it seems to screw things up in a number of ways, including that it keeps misc/textarea.js from getting loaded, which, one way or another, causes up teaser.js to hide the ENTIRE body field, not just the part below the "split cursor" element. Or something like that -- as you can tell, I'm on pretty thin ice regarding what's going on here.

Anyway, once I disabled the handler above, all became well. I'll let others with more knowledge about these internals figure out if I shot myself in the foot and got what I deserved, or if there's an issue here that ought to be addressed.