problem with queryprogram result limit

Hi,

I'm using the queryprogram router to process dynamic email addresses
(those are build out of simple expressions like x_and_y@mydomain.com).
My router program usually returns either a REDIRECT or a FAIL. Overall
the system works pretty well, however I do have the problem, that for
some expressions I generate REDIRECT lists which are longer than 1023
bytes. Any idea how I can work around that? I solution I could think of
would be to use the router several times and having the queryprogram
generate parts of the REDIRECT list, but I don't know how to do that.
(I do have an upper limit for the length of the result, but its bigger
than 1023.)

Thanks for any hints,

André

PS: I'm running debian stable (sarge) with exim4 -bV:
Exim version 4.50 #1 built 27-May-2005 08:08:19
Copyright (c) University of Cambridge 2004
Berkeley DB: Sleepycat Software: Berkeley DB 4.2.52: (December 3,
2003)
Support for: iconv() IPv6 GnuTLS
Lookups: lsearch wildlsearch nwildlsearch iplsearch cdb dbm dbmnz
dsearch nis nis0 passwd
Authenticators: cram_md5 plaintext
Routers: accept dnslookup ipliteral manualroute queryprogram redirect
Transports: appendfile/maildir/mailstore autoreply lmtp pipe smtp
Fixed never_users: 0
Configuration file is /var/lib/exim4/config.autogenerated

My current solution is to use a patched exim, where I increased the
buffer to 16384 characters. This is much more than I'll ever need. I
think its fine to fix the buffer size, i.e. set a maximum as its done
with the execution time ulimit as well, but it would be great to make
the buffer size a config option. Any thoughts?

André