The problem is that 1.6.19-1 is listening on ipv6 as well, and that makes the test suite fail to start another copy due to "address already in use":
@@__xproc_block_delimiter__@@ slab class 1: chunk size 96 perslab 10922 (...) failed to listen on TCP port 11211: Address already in use 1.6.18-1 only listened on 127.0.0.1:11211. Best way to fix? Not sure yet. Maybe kill the system-provided memcached before running the test? That might need to have the test run as root, at least to execute that action, which is annoying...
