[Exim] Regular expressions Help

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Hi,

I'm running exim 3.2x in quite a custom environment.

I have the following directors and transport :

DIRECTORS
=========
# This director matches local user mailboxes.
AddressChange:
driver = smartuser
new_address = HPS+$local_part@$domain
new_director = LocalDomainUser


# Local domain user
LocalDomainUser:
driver = localuser
transport = local_delivery

TRANSPORTS
===========

local_delivery:
driver = appendfile
file = /var/spool/mail/$local_part
delivery_date_add
envelope_to_add
return_path_add
group = exim
user = $local_part
mode = 0660

As you can see my director, AddressChange mangles the local_part to have the text 'hps+' prepended. At the moment, the transport is correctly generating mail box files all in lower case, ie :
/var/spool/mail/hps+pmiles

I need exim to generate mail box files in mixed case, where the 'hps' is always in upper case. ie :
/var/spool/mail/HPS+pmiles

Is this possible, and if so how?

Many thanks in advance,

Paul
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