I have a site created in php, the header tags are loaded in two separate files. One loads for the front page, so I get one set of tags for that, and the other loads for all other pages. This means that I can only optimise one set of keywords for the front page and one set for all the other pages.

Given that the same header file loads with the same tags for all pages other than the front page how can I set dynamic tags which are specific to the page loading but doesn’t look fishy to the search engines and in particular the most holy Google?

Thanks in advance for your assistance?