Trouble installing

After following the instructions explicitly
Copied the files into their directories and did not see the plugin in plugins section.
Then I uploaded the ZIP file via the plug add tool.
The plugin appreared, plus frame work, etc...
I checked and verified DB tables when I click on the activate plugin?

Fatal error: Call to undefined function get_admin_page_title() in /public_html/wp-admin/admin-header.php on line 12

Any ideas why.

This happened on both WPMU 2.9.1 & 2.9.1.1