Cannot use string offset as an array

On PHP 5.0 Using Drupal 5 patch submitted by nkoponen on January 28, 2007 - 04:57

Error occurs when submitting user/n/edit for non-admin user with certain user fields denied:

Can not deny: timezone , signature

Can Deny: picture

Fatal error: Cannot use string offset as an array in C:\www\drupal5\sites\all\modules\user_readonly\user_readonly.module on line 205

line 205: $form[$group][$key]['#attributes']['disabled']= true;

Also submitted this at end of htmlspecialchars() update. I'm getting different errors on php 4 & 5, could be related, but including "deny timezone" breaks PHP5, works on PHP4.3