[Exim] Generic System Filter

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Hello,

We are currently using Nigel's generic Exim system filter to reject attachments
with the "usual-suspect" extensions and it seems to work fine. Yesterday however
we had one message pass straight through it.

The filter is working for other ".exe's" but the one included below managed to bypass it.

Can anybody, who understands the reg. exp. within the filter, care to possibly suggest
why this has happened.

Many thanks
Martyn
University of Glamorgan

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Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="jrvifgij"

--jrvifgij
Content-Type: multipart/related; boundary="glfluiatlrgapacqg";
    type="multipart/alternative"

--glfluiatlrgapacqg
Content-Type: multipart/alternative; boundary="xrcdfhyfxly"

--xrcdfhyfxly
Content-Type: text/plain
Content-Transfer-Encoding: quoted-printable

--xrcdfhyfxly
Content-Type: text/html
Content-Transfer-Encoding: quoted-printable

--xrcdfhyfxly--

--glfluiatlrgapacqg
Content-Type: image/gif
Content-Transfer-Encoding: base64
Content-ID: <bmixuww>

--glfluiatlrgapacqg
Content-Type: image/gif
Content-Transfer-Encoding: base64
Content-ID: <ovmckcz>

--glfluiatlrgapacqg--

--jrvifgij
Content-Type: application/x-msdownload; name="INSTALLER.exe"
Content-Transfer-Encoding: base64
Content-Disposition: attachment

--jrvifgij--
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