[exim] Maildir Quota excluding Trash folder.

All,

I'm delivering a message to the Trash folder in a Maildir with quotas
enabled via an exim filter. I have the following set on the transport
doing the delivery, but the maildirsize file is being incremented when the
message is delivered.

maildir_quota_directory_regex = ^(?:cur|new|\.(?!Trash).*)$

I copied this from the documentation, which says this should cause the
Trash folder to be exempt from quotas.

Any help would be appreciated.

--Derek