Apache add header to request according to different domain
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There are http://foo.com and https://secur.foo.com.

If request from https://secur.foo.com, I want to and some external information to request headers.

Could some body tell me how to complete above requirement?

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I tried to use the following code to add header to request

    Header add myheader "myvalue"
    RequestHeader set myheader2 "myvalue2"

But I only find "myheader:myvalue" in response, how to make "myheader2" shows in request? 