saeeded on "Modify printHeadTitle() function manually"

hi to all
I want to modify meta tags on the (index,album,image,search,archive) header.
in theme>basic> Just able to be modify under PrintHeadTitle() function and if I want put my meta tags in theme files, meta tags get duplicated.
Now I want to modify ZenPhoto "printHeadTitle() function manually and use DB value in meta tags for build different content, Keyword or description.
in current case ZenPhoto make album and pages with same description and most time "album" script function build pages with null "Meta tags>Keyword".
.
thank for help me how to modify printHeadTitle() function.

thanks
sorry for my english
edrisi