[squid-users] Questions or problems in transition from SQUID-2.5STABLE14 to SQUID-2.6STABLE1

I tried to upgrade two of our main proxies from
squid-2.5.STABLE13/squid-2.5STABLE14 to squid-2.6STABLE1

One is a SuSE Linux 10.0 - x86-32, the other is a SuSE 9.3 - x86-64.
Both are connected to a hardware loadbalancer and have about 3000
clients and about 100-150 requests per second each.

While the 32 bit machine is running stable, the other one (64-bit)
restarts often with Segmentation Violations.

Both are configured with nearly the same parameters (with the exception
of optimization and 32/64-bit)
 

Before that, both machines ran stable for months with the epoll patches
from devel.squid-cache.org. I switched back on the 64-bit machine, and
the squid-2.5.STABLE14 runs stable again.

Is it possible, that there is still a 64-bit Problem in
Squid-2.6STABLE1?
I couldn't get a core dump of the Squid 2.6.STABLE1 - x86_64, perhaps
because it runs multithreaded (with aufs).

---
The other effect:
The cache digests aren't longer working, both with the 32 bit and the 64
bit system, also  I enabled them with -enable-cache-digests.
In the cache log, I can find an error like "temporary disabling digest
from vproxy.. (not found)", in the access.log the digest request is
responded with a 404 error.
Is there any change in the syntax of cache digests in squid.conf, so
that this could be expected?
Thanks in advance,
Martin