Limiting squid cache size

We are using squid-2.0-PATCH1 and I have set up multiple
cache directives.

cache_dir /cache1 1000 16 256
cache_dir /cache2 1000 16 256
cache_dir /cache3 1000 16 256
cache_dir /cache4 1000 16 256

but the individual caches are now growing past 2 gigs.
Is there any related configuration option that I have missed ?

Mike
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Michael Hockey
                                Deakin Offices (DKN-N1-OA1)
 _--_|\ 109 Kent Street , Deakin ACT 2600
/ \ Phone: +61 02 6265 8940
\_.--.*/ACT Fax: +61 02 6265 8587
      v Email: mqh@defweb.defence.gov.au
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Received on Mon Dec 07 1998 - 16:09:17 MST