sslWriteServer: write failure problem ??? memory is never release ???

Hi,

We have trouble using our squid proxy 2.2STABLE5, on linux RH6.0, because it seems to allocate memory which is never release ?
After a reboot the server (512Mo) has more than 350Mo available memory. Our Squid proxy is working properly a few days, however, free memory decreases every hours and when there is only roughly 3 Mo left, squid hangs with the following logs in cache.log file:

2000/06/22 11:28:35| sslStart: 'CONNECT interactif.creditlyonnais.fr:443'
2000/06/22 11:28:35| sslConnected: FD 46 sslState=0x86366d0
<loop -- a lot of these lines which load the CPU up to 99%, because squid does many tries before the "broken pipe">
2000/06/22 11:28:36| sslWriteServer: FD 29, 86 bytes to write
2000/06/22 11:28:36| sslWriteServer: FD 29, -1 bytes written
2000/06/22 11:28:36| sslWriteServer: FD 29: write failure: (11) Ressource temporairement non disponible.
</loop>
2000/06/22 11:28:36| sslWriteServer: FD 46, 86 bytes to write
2000/06/22 11:28:36| sslWriteServer: FD 46, -1 bytes written
2000/06/22 11:28:36| sslWriteServer: FD 46: write failure: (32) Relais brisé (pipe).
2000/06/22 11:28:36| sslServerClosed: FD 46
2000/06/22 11:28:36| sslClientClosed: FD 25
2000/06/22 11:28:36| sslStateFree: sslState=0x86366d0
and again ....

I have located in the source (src/ssl.c, line 265 : sslWriteServer) the write(fd, sslState->client.buf, sslState->client.len) which return -1 !

What can I do ? Our users mostly uses SSL restricted sites.

I do not know where to seek now.
Please help.

Thanks

--
Sébastien