RewriterRule not working for alias domain name

Hi

We are working on a multilingual website. it has five URL (one
original and four alias) for all the five languages. we are using
RewriterRule in web.config to rewrite the Url. All this working fine
on my local machine but when we have upload it on live we are facing a
problem. that RewriteRule doesn't working for the alias name. it means
when we request any page with alias name RewriterRule not works
properly

Example :

main website is Webcarhire.com
and alias is webcarhire.fr

when I request a page webcarhire.com/contactus.htm - the RewriterRule
works fine

but

when i request a page webcarhire.fr/contactus.htm - the RewriterRule
is not working

Note : I have assign the worker process to .htm and .html page in ISS
and also
I have add following rule in web.config
<RewriterConfig>
<Rules>
<RewriterRule>
<LookFor>[^\.fr].+\.htm</LookFor>
<SendTo>~/BlankPage.aspx</SendTo>
</RewriterRule>
</Rules>
</RewriterConfig>




Please let me know if any one have solved this problem.

.