[SOLVED] site admin error @ 'thumbnails' link

Just downloaded G2 today (newest mar 23 version)... everything running smoothly, except in the site admin, if I click "Thumbnails" on the left nav-bar, I get the error: Fatal error: Call to undefined function: getmimemap() in /home/photos/public_html/modules/thumbnail/ThumbnailSiteAdmin.inc on line 134

on a blank page.

whatsup?

Editted: further to this, I've noticed that if I had the "Square Thumbnails" module activated, and then added pics to an album, they have square thumbnails, as expected.. however, if I deactivate this module, then try to "recreate thumbnails" in the "edit album", the thumnails stay square! only newly added pictures get normal thumnails...
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Gallery URL (optional):
Gallery version: gallery2-2005-03-23
Webserver (with version): Apache/1.3.27 (Unix) (Red-Hat/Linux) mod_perl/1.26 PHP/4.3.3 FrontPage/5.0.2 mod_ssl/2.8.12 OpenSSL/0.9.6b
Datatabase (with version): mysql 3.23.58
PHP version (eg 4.2.1): 4.3.3
phpinfo URL (optional):
Graphics Toolkit(s): just GD
Operating system: win xp sp2 pro
Web browser/version: ie 6.0