Evolution 1.0 TinyMCE language string substitution problem

I’ve been working successfully with Evolution 1.0.0 but noticed a problem in Advanced mode of TinyMCE (version 3.2.4.1). Certain pages do not get strings such as "{#advanced_dlg.charmap_title}" replaced with the appropriate language string (even English). For example, when I click "Insert Custom Character" from the TinyMCE Editor, I get a popup window with the title "{#advanced_dlg.charmap_title}". When I look at the source HTML of the popup window (charmap.htm), it’s obviously missing some language string substitutions because I find stuff like this:
<td colspan="2" class="title">{#advanced_dlg.charmap_title}</td>
Somewhere that {...} should have been replaced with "Select custom character" but it’s not.

I can’t tell if this is a TinyMCE problem or a MODx problem or my problem. I’m not missing any language files because everything else works OK - popup help text, etc. I’m using Firefox and my "Tools/Error Console" is not reporting any Javascript errors. It seems to be just some of the Advanced mode TinyMCE buttons. Any ideas?