conditional based on useragent

[kevinmiddleton]

I want to write a conditional based upon if the Yahoo bot is visiting, but I cannot find the correct variable. Any ideas?

e.g. <If condition="$correct_variable_for_useragent = correct_name_for yahoo_slurp">

Thanks

[Jake Bunce]

<if condition="$_SERVER[HTTP_USER_AGENT] == '[color=red]string for yahoo[/color]'">

</if>