I had the same thing when I tried to update to the latest P2. I found no solution but was told that it does not work if your server still has PHP4.
If (like me) you are stuck with php4, you can still use the old theme but as wordpress is going only php5 you’ll have more and more troubles w/ other updates too See this thread
inspiraven .. THANK YOU for your response. You helped me solve the problem. I use 1and1 for hosting and found the following information so that I could make sure that my site uses php5. Hope you can use the same information where you host your site(s).
You may choose to simply name the script with the .php5 file extension if there are only a few scripts that require PHP5. If you don’t want to rename all your scripts to .php5, you can do the create a .htaccess file (or edit the existing .htaccess file, if you already have one). You can create this file using a text editor such as Notepad, WordPad, vi, nano, etc. and place the following line in the text file:
AddType x-mapp-php5 .php
Save the text file as .htaccess in the folder where you need to use PHP5 (or upload the file to the correct folder). The settings specified in the .htaccess file are recursive meaning that the settings will apply to the current folder where the file is saved as well as all subfolders.
