Apparently a few users of the mod_placehere module get this error message:
* JHTMLicon not supported. File not found
I cannot reproduce this (using Joomla 1.5.9 on Windows Vista/Apache 2/PHP 5 and mod_placehere version 1.2.2), but I do not simply want to ignore the issue, so if you get this error on your site please contact me with version information of your software.
I’m working on it and will try do release a bugfix next week.
It seems the problem only occurs with some placehere templates. I get it with Beez but not with Default.
There is a discussion at http://forum.joomla.org/viewtopic.php?p=1663346 which might be useful.