Unable to match expression inside If directive no matter what

Question

I have been trying for the past 3 hours trying to match an if statement to define a variable within httpd.conf with no success:

<If "%{HTTP_HOST} =~ /[a-z]+/i">
  Define test_value "A"
</If>
<Else>
  Define test_value "B"
</Else>

I have tried:

<If "%{HTTP_HOST} !~ /[a-z]+/i">
<If "%{HTTP_HOST} == 'mysite.com'">
<If "%{HTTP_HOST} != 'mysite.com'">
<If "%{HTTP_HOST} == ''">
<If "%{HTTP_HOST} != ''">

All matching the else case. What could be wrong?